M S Erskine's research while affiliated with Boston University and other places

Publications (81)

Article
In female rats, vaginal-cervical stimulation (VCS) received during mating induces bicircadian prolactin surges that are required for the maintenance of pregnancy or pseudopregnancy (PSP). The neural circuits that transmit VCS inputs to the brain have not been fully described, although mating stimulation is known to activate medullary noradrenergic...
Article
We sought to examine AMPA receptor (AMPAR) function in the medial posterodorsal amygdala (MePD), as glutamate neurotransmission is critical for the neural response to vaginal-cervical stimulation that initiates pregnancy or pseudopregnancy. Female rats were infused with the AMPAR antagonist CNQX or vehicle directly into the MePD via bilaterally imp...
Article
Pseudopregnancy (PSP) is a neuroendocrine reflex triggered by vaginocervical stimulation similar to the neuroendocrine response of early pregnancy and is characterised by short-term neural activity, resulting in long-term neuroendocrine responses that cause repeated release of pituitary prolactin (PRL) over many days. PSP is a useful model to study...
Article
Female rats require a sufficient amount and pattern of vaginal-cervical stimulation to initiate neuroendocrine changes required for the successful implantation of a fertilized ovum in the uterus. These changes are characterized by twice daily prolactin surges that last 10-12 days. Following a sterile mating, the endocrine changes are still observed...
Article
The ventrolateral region of the ventromedial hypothalamus (VMHvl) plays an essential role in female sexual behavior. Oxytocin (OT) is released from the paraventricular nucleus to downstream sites such as the VMHvl to facilitate female sexual behavior and shows characteristics of a prolactin (PRL)-releasing factor. During mating, vaginal cervical st...
Article
Pseudopregnancy (PSP) in the female rat is a neuroendocrine condition that is induced by repeated and intermittent vaginocervical stimulation received during mating and involves the expression of bicircadian prolactin surges and cessation of normal estrous cyclicity for 10-12 days postmating. The temporal patterning and number of intromissions rece...
Article
The ventromedial hypothalamus (VMH) is an oestrogen-responsive area known to facilitate female sexual behaviour in the rat. The VMH is innervated by noradrenergic neurones projecting from the brain stem, and it has been demonstrated that noradrenaline receptor activation in the VMH plays a role in the expression of the lordosis reflex. Noradrenalin...
Article
Full-text available
Female rats modulate the number and interval between the intromissions the female receives during mating. This patterned vaginocervical stimulation (VCS) is critical for triggering long-term changes in prolactin (PRL) secretion necessary for pregnancy or pseudopregnancy (P/PSP). Previous work has shown that NMDA receptor activation in the posterodo...
Article
Sexual partner preference in female rats has been difficult to establish experimentally because the vaginocervical stimulation the female receives during the preference test can be rewarding or aversive depending on the context. G. A. Coria-Avila, A. J. Ouimet, P. Pacheco, J. Manzo, and J. G. Pfaus (2005) reported that female rats can be conditione...
Article
Neurons within the posterodorsal medial amygdala of female rats are known to process vaginocervical stimulation received during mating through N-methyl-D-aspartate channel activation, conveying information to downstream hypothalamic cell groups that modulate neuroendocrine function. Stimulation of these neurons with an excitatory amino acid cocktai...
Article
In the female rat, stimuli from the uterine cervix and vagina are carried to the brain areas involved in the mating-induced pseudopregnancy (PSP) response via the ventral noradrenergic bundle. Noradrenergic neurons projecting through this tract synapse in many forebrain areas including the amygdala, and neurons in the posterodorsal medial amygdala...
Article
In the female rat, the integrity of the ventral noradrenergic bundle (VNAB) is necessary to carry stimuli from the uterine cervix and vagina to brain areas involved in mating-induced pseudopregnancy. Because adrenal hormones are known to alter noradrenergic function, we examined whether adrenalectomy altered mating-induced Fos expression in the A1...
Article
In cycling female rats, vaginocervical stimulation (VCS) received naturally during mating or by artificial mechanical stimulation induces neuroendocrine and behavioral responses that are critical for reproduction, including bi-circadian prolactin surges which result in pregnancy or an 8-14-day diestrous period called pseudopregnancy (PSP). Followin...
Article
Two experiments assessed the effects of neonatal testosterone treatment on paced mating behavior and conditioned place preference in female rats. In both experiments, females received s.c. injections of 5.0 microg testosterone propionate or oil vehicle at three days postpartum. As adults, females were ovariectomized and given s.c. injections of 10...
Article
In the estrous female rat, mating stimulation induces an acute surge of prolactin (PRL) within 20 min after mating followed by the onset of twice-daily PRL surges which persist for an 8- to 13-day period of acyclicity called pseudopregnancy. In Experiment 1, we examined whether the release of adrenal hormones after mating modulates mating-induced P...
Article
Full-text available
In rats of both sexes, mating stimulates neuronal activity in forebrain areas that are also activated by stress. Hypothalamic cells in the arcuate (ARC) and paraventricular (PVN) nuclei synthesize hormones or peptides whose levels are altered by adrenalectomy. In this experiment, we examined whether the mating-induced expression of c-FOS in the for...
Article
Feminine sexual behavior has been used extensively as a model system for understanding the mechanisms by which hormonal and neural signals interact at the cellular level to modulate behavior. Synthesis of much of the early behavioral and neuroendocrine work on this system with new cellular and molecular findings suggests that a fruitful direction t...
Article
Full-text available
In female rats, genitosensory stimulation received during mating initiates twice-daily prolactin (PRL) surges, a neuroendocrine response that is the hallmark of early pregnancy or pseudopregnancy (P/PSP). Nocturnal and diurnal PRL surges are expressed repeatedly for up to 2 weeks after copulation, suggesting that a neuroendocrine memory for vaginoc...
Article
This study examined the role of the posterodorsal medial amygdala (MePD) in the control of prolactin secretion in gonadally intact female rats 20 min after mating, during the oestrous cycle, and during early pregnancy/pseudopregnancy (P/PSP). Cycling females received bilateral infusions of an excitotoxic dose of N-methyl-D-aspartate (NMDA) or vehic...
Article
Vaginocervical stimulation (VCS) received during mating is known to induce analgesia and to suppress FOS-immunoreactivity (FOS-IR) in lumbar spinal cord. However, it is not known whether this suppression of FOS-IR reflects inhibition of afferent nociceptive input. The present studies examined whether two immediate-early gene (IEG) products, FOS and...
Article
The transneuronal tracer, pseudorabies virus (PRV), was used to identify pathways from the uterine cervix which may be involved in induction of analgesia and abbreviation of estrus by vaginocervical stimulation. In Experiment I, PRV immunoreactivity (PRV-IR) in brain and spinal cord was examined 3-5 days after injection into the cervix of ovariecto...
Article
Full-text available
Previous studies have implicated oxytocin (OT) in the control of surge-type PRL secretion in the pregnant and pseudopregnant rat. The present studies examined the relationship between mating-induced activation of OT neurons in the paraventricular (PVN), supraoptic (SON), and anterior commissural (ACN) nuclei and PRL secretion. Activity within OTerg...
Article
When estrous female rats control or pace (P) their sexual contacts with males, several neuroendocrine and behavioral responses to mating occur that are not observed or are greatly attenuated after nonpaced mating. The present study examined whether the distribution and amount of FOS immunoreactivity (FOS-IR) induced in brain by mating would be alte...
Article
Pregnane neurosteroids may initiate sexual receptivity not only via actions at intracellular receptors, but by affecting gamma-aminobutyric acid (GABA) receptor complexes (GBRs). To investigate whether GBR-mediated actions of an androgenic neurosteroid 5 alpha-androstane-3 alpha, 17 beta-diol (3 alpha-androstanediol; 3 alpha-Diol) may influence the...
Article
We investigated whether 5 alpha-androstane-3 alpha, 17 beta-diol (3 alpha-androstanediol; 3 alpha-Diol), a neurosteroid whose effects are primarily inhibitory to sexual behavior, may act through interactions with gamma-aminobutyric acid (GABA) receptor complexes (GBRs) in the medial basal hypothalamus (MBH) and the preoptic area (POA). In Experimen...
Article
In female rats, vaginocervical stimulation induces neuroendocrine responses necessary for pregnancy as well as analgesia to a variety of noxious stimuli. In this study, Fos immunocytochemistry was used to detect vaginocervical stimulation-induced changes in the activity of spinal neurons at levels T11-S3, segments known to receive afferent input fr...
Article
The effects of differential mating stimulation on sexual behavior and estrus length were examined in cycling rats that could or could not self-regulate, or pace, the timing of sexual contact. Female rats (Rattus norvegicus) received 30 paced, 30 nonpaced, or 15 nonpaced followed by 15 paced intromissions during mating tests. Decreases in sexual res...
Article
Ovariectomized rats with cannula over the medial basal hypothalamus (MBH) received implants of 3 alpha-diol conjugated to bovine serum albumin (BSA; 3 alpha-diol:BSA), free 3 alpha-diol diluted with BSA (3 alpha-diol&BSA), progesterone (P) conjugated to BSA (P:BSA), free P diluted with BSA (P&BSA), or BSA alone. 3 alpha-diol:BSA or 3 alpha-diol&BSA...
Article
Ovariectomized rats with cannula over the medial basal hypothalamus (MBH) received implants of 3α-diol conjugated to bovine serum albumin (BSA; 3α-diol:BSA), free 3α-diol diluted with BSA (3α-diol&BSA), progesterone (PRE) conjugated to BSA (PRE:BSA), free PRE diluted with BSA (PRE&BSA), or BSA alone. 3α-diol:BSA or 3α-diol&BSA facilitated receptivi...
Article
In the female rat, gonadal and adrenal progestins and androgens modulate sexual receptivity and in turn, their levels increase in response to mating stimulation. Paced mating, in which the female controls the timing of sexual contacts with the male, is particularly effective at eliciting acute increases in progesterone (P) and 5 alpha-Androstane-3...
Article
Vaginal perforation, or patency, is shown to be highly correlated with levels of estradiol in plasma of the female meadow vole, Microtus pennsylvanicus. The use of vaginal patency as an indicator of receptivity of females is supported by this correlation.
Article
In the rat, vaginocervical stimulation (VCS) received during mating is required for the subsequent expression of 10-12 days of twice-daily prolactin surges that are necessary for pregnancy or pseudopregnancy (PSP). This temporal separation of sensory stimulus and neuroendocrine response suggests that a mnemonic of the vaginocervical stimulation is...
Article
The efficacy of 5 alpha-androstane-3 alpha,17 beta-diol (3 alpha-Androstanediol; 3 alpha-Diol) and 4-pregnen-3,20-dione (progesterone; P) in promoting analgesia was investigated. Ovariectomized rats received daily injections of 3 alpha-Diol (0.6, 3.0, 6.0 and 7.5 mg/kg) or vehicle and twice daily injections of estradiol-17 beta (E2: 1 microgram) fo...
Article
This paper aims to study the relationships between telecommunications and international movements of factors such as exports, imports and tourists in Turkey. A multiple regression analysis is used to analyze the relationship between international telephone calls and international movements. Incoming tourism is the dominant movement explaining growt...
Article
To determine whether neighbor familiarity can affect reproduction, we studied the relationship between familiarity, odor preference, and plasma estradiol levels in the meadow vole, Microtus pennsylvanicus. Bedding was switched between pairs of female meadow voles for 2 wk to allow them to develop olfactory familiarity. When familiarization was comp...
Article
Previous research in this laboratory has shown that chronic treatment of adult male rats with an anabolic-androgenic steroid (AAS) produced anxiolytic behavior and increased the functional response of cortical gamma-aminobutyric acid(A) (GABA(A)) receptors. The experiments reported here were aimed at further characterizing the effect of chronic AAS...
Article
Vaginocervical stimulation received either during mating or by artificial mechanical means has been shown to induce FOS expression in medial amygdala, preoptic area, hypothalamus, and midbrain of female rats. While mating-induced increases in FOS-like immunoreactivity (FOS-IR) have been shown to require intromissive stimulation from males, the patt...
Article
Study of the mechanisms by which VCS induces the 10-13 days of twice-daily PRL surges, while at present incompletely understood, will help us to answer several more general neural and endocrine questions: 1) what similarities exist between the suckling-induced and VCS-induced changes in pituitary hormone release, and what central and peripheral mec...
Article
The metabolite of dihydrotestosterone, 5 alpha-androstane-3 alpha, 17 beta-diol (3 alpha-Diol), is a potent inhibitor of estrogen-induced gonadotropin and prolactin secretion and lordosis behavior in the female rat. This study examined whether 3 alpha-Diol can counteract the ultrastructural changes which are known to occur in the ventromedial nucle...
Article
The metabolite of dihydrotestosterone, 5α-androstane-3α,17β-diol (3α-Diol), is a potent inhibitor of estrogen-induced gonadotropin and prolactin secretion and lordosis behavior in the female rat. This study examined whether 3α-Diol can counteract the ultrastructural changes which are known to occur in the ventromedial nucleus (VMN) of the hypothala...
Article
The effects of differential mating stimulation on fertility in rats were examined by mating pro-oestrous females for one ejaculatory series in tests in which they could or could not self-regulate, or pace, the timing of intromissions received by males. Females were autopsied on days 7, 14 or 21 after mating, or on the expected day of birth to confi...
Article
In the female rat, stimulation of the uterine cervix (CS) during mating or by artificial means induces daily diurnal and nocturnal surges in prolactin (PRL) secretion which, in the absence of fertilization, result in an 12-day anestrous period called pseudopregnancy (PSP). The amount or type of mating stimulation received by the female during matin...
Article
Previous research has shown that mating induces the expression of the immediate-early gene, c-fos, as detected by the increased presence of nuclear FOS-like immunoreactivity (FOS-IR), in specific forebrain regions of both male and female rats. In the male both olfactory-vomeronasal (O/V) and genital/somatosensory (G/S) inputs appear to contribute t...
Article
In order to identify brain areas which receive afferent genitosensory input important for mating-induced prolactin release, we compared numbers of Fos-immunoreactive (Fos-IR) cells in brains of intact estrous females 1 h after differential mating stimulation. Numbers of Fos-IR cells were approximately 3-fold higher in the preoptic area (POA), media...
Article
Genitosensory stimulation received during mating initiates neural and endocrine changes necessary for pregnancy. The present study examined sites of induction of the proto-oncogene, c-Fos, after mating in the cycling female rat to determine neural sites activated by such stimulation that might be involved in pregnancy initiation. Two groups of cycl...
Article
Six experiments were carried out to determine whether dihydrotestosterone (5 alpha-androstan-17 beta-ol-3-one; DHT) acts to inhibit oestradiol (OE2)-induced lordosis behaviour after its metabolic conversion to 5 alpha-androstane-3 alpha,17 beta-diol (3 alpha-androstanediol, 3 alpha-Adiol). In experiments 1 and 2, ovariectomized rats were treated wi...
Article
Two experiments examined whether the pudendal and pelvic autonomic nerves are important for pacing behavior shown by the female rat during mating. Ovariectomized female rats received bilateral transection of the pudendal (Pux), pelvic (Pex), or pudendal and pelvic (Pu + Pex) nerves or were sham-operated (Shx). Lordotic behavior, precopulatory solic...
Article
The present experiments sought to characterize the particular stimuli received during mating in the female rat which induce acute increases in luteinizing hormone (LH) and prolactin (PRL) following copulation. Comparisons were made between cycling females mated on the evening of proestrus in partitioned chambers in which spontaneous patterns of app...
Article
The present experiments were carried out to determine what physiological conditions are responsible for the acute increases in serum levels of 5 alpha-androstane-3 alpha, 17 beta-diol (3 alpha-androstanediol, 3 alpha-Adiol) which are seen in the intact estrous female rat within 15-30 min after mating. Blood samples were obtained from proestrus rats...
Article
The present experiment was designed to examine whether changes occur during the course of behavioural oestrus in the sensitivity of the female to copulatory stimulation and in patterns of sexual behaviour which might influence the likelihood of luteal maintenance. Cyclic female rats were mated on the evening of pro-oestrus (21:00 h) or early on the...
Article
Abstract Intravenous infusions of the opioid receptor antagonist, naloxone, caused a significant rise in luteinizing hormone (LH) pulse frequency in male and female ferrets which had been gonadectomized 10 days earlier while in breeding condition; mean LH concentrations and LH pulse amplitudes were not affected. By contrast, naloxone failed to stim...
Article
Experiments were conducted to assess the time course of behavioral and endocrine changes which occur in female ferrets as they switch from estrus to the pseudopregnant state. Significant reductions in females' acceptance of neck gripping by a stimulus male (receptivity) and in their latency to approach a stimulus male in an L-maze (proceptivity) we...
Article
Implanting testosterone (T) subcutaneously over Postnatal Days 5-20 masculinized sexual behavior, reduced proceptive responsiveness, and shifted sexual preference more readily in male than in female ferrets gonadectomized on Day 5. This enhanced sensitivity of males to neonatal T was best duplicated in females exposed transplacentally to T over Emb...
Article
Data are reviewed concerning the display of solicitation behaviors in the estrous female rat, including precopulatory hopping, darting, and ear wiggling, and the pacing of copulatory contacts through patterns of approach toward and withdrawal from a sexually active male rat. Observations made under semi-natural and laboratory conditions suggest tha...
Article
Although 5 alpha-dihydrotestosterone (DHT) is a potent inhibitor of lordosis behavior in ovariectomized estrogen-primed female rats, the mechanism(s) by which this steroid has this action is unknown. The present experiments sought to determine whether DHT inhibits lordosis by preventing the known facilitatory actions of luteinizing hormone-releasin...
Article
When estrous female rats regulate or pace (P) the timing of vaginal intromissions received from males during mating, the stimulation is more effective in inducing luteal function and abbreviating the period of receptivity than is nonpaced (NP) stimulation. The present studies examined whether the coital stimuli necessary for each of these functiona...
Article
This study examined the contribution of the superior ovarian nerve (SON) to estrous responsiveness and ovarian function in cycling rats. Section of the SON was carried out at 1100 on proestrus, and lordotic responsiveness was measured at 1500, 1700, and 2100 on that day and at 0900, 1200, and 1500 on the day of estrus. SON section decreased lordosi...
Article
The present studies examined the patterns of circulating testosterone (T) within 0-24 h after birth in male and female ferrets along with concomitant changes in neural aromatase activity and hypothalamic concentrations of estradiol (E2). Plasma and brain samples were obtained 0 and 2 h (cesarean delivery) or 0, 2, 12, and 24 h (natural delivery) af...
Article
The cycling female rat spontaneously regulates (paces) the amount and timing of cervical-vaginal stimulation received during mating. Female pacing of coital contacts increases the ability of vaginal intromissions to induce luteal function and to abbreviate the period of behavioral estrus. In the experiments reported here, we examined whether paced...
Article
Sex differences in the pulsatile secretion of LH were examined in male and female ferrets after mating. Female ferrets which were either gonadally intact and in estrus or gonadectomized and maintained on a pulsed regimen of daily estradiol (E2) injections exhibited a prolonged rise in plasma LH, characterized by an elevation in mean LH levels and a...
Article
Administration of the synthetic steroid, 17 beta-hydroxy-17 alpha-methyl-estra-4,9,11-triene-3-one (methyltrienolone, R1881), which is an androgen receptor agonist not metabolized in vivo, at doses of 400, 800 or 2400 micrograms/kg s.c. in propylene glycol stimulated mounting and ejaculation only slightly in sexually experienced castrated rats. A s...
Article
Administration of the synthetic steroid, 17β-hydroxy-17α-methyl-estra-4,9,11-triene-3-one (methyltrienolone, R1881), which is an androgen receptor agonist not metabolized in vivo, at doses of 400, 800 or 2400 μg/kg s.c. in propylene glycol stimulated mounting and ejaculation only slightly in sexually experienced castrated rats. A similar low level...
Article
Experiments were carried out to examine the mechanism whereby 5 alpha-dihydrotestosterone (DHT) antagonizes the stimulatory effects of estrogen plus progesterone (P) on sexual receptivity (lordosis) in the ovariectomized rat. Estradiol (E2; 1 microgram s.c. in 10% ethanol) was administered in a discontinuous (pulsed) treatment regimen thought to mi...
Article
A series of experiments focused on the masculine coital behaviors controlling pituitary luteinizing hormone (LH) secretion and reflex ovulation in the estrous female ferret. An initial experiment investigated which coital stimuli from the male are required to induce ovulation. It was found that corpus luteum formation, which served as an index of o...
Article
Male ferrets castrated on postnatal day 5 displayed significantly lower levels of neck gripping, mounting, and pelvic thrusting behavior than groups of males castrated on postnatal days 20 or 35 when tested in adulthood after treatment with testosterone (T). Administering a high dosage of T via sc Silastic capsules to ovariectomized female ferrets...
Chapter
Over the past 25 years much evidence has accumulated (reviewed in Baum 1979) to show that sexual dimorphisms in mammalian social behaviour ultimately derive from dimorphic patterns of sex steroid hormone secretion and brain action during critical perinatal periods of development. It is well established that a primary source (in the view of many inv...
Article
The concentrations of oestradiol and oestrone in peripheral plasma of male and female ferrets 5 days before and 7, 15 and 30 days after birth were measured. Both steroids were present in high concentrations prenatally. Much lower levels were found in samples collected on day 7 and later, when the concentrations were similar to those of adult gonade...
Article
Serotonin (5-HT) and 5-hydroxy-indoleacetic acid (5-HIAA) levels were measured in brain regions of ovariectomized, steroid-primed rats at the end of behavioral estrus. At the onset of behavioral estrus three groups of rats received coital stimulation which included (1) mounts without penile intromission only, (2) temporally-controlled (paced) mount...
Article
Concentrations of testosterone (T) and 5 alpha-dihydrotestosterone (DHT) were measured in plasma collected from male and female ferrets at eight perinatal ages, spanning the period when behavioral sexual differentiation occurs in this species. Concentrations of T were significantly higher in males than in females 5 days before birth (day -5) and on...
Article
The dose-dependent inhibition of lordosis by 5 alpha-dihydrotestosterone propionate in ovariectomized female rats treated concurrently with estradiol benzoate was attenuated neither by intracranial 6-hydroxydopamine injections which reduced dopamine concentrations by approximately 70% in septum or 75% in both septum and n. accumbens septi nor by el...
Article
Steady-state concentrations of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) in anterior hypothalamus (AH), preoptic area (POA), suprachiasmatic nucleus (SCN) and ventromedial nucleus (VMH) were equivalent 30 days after castration or sham operation in male rats killed at either the middle of the light or dark periods of a 12 :...
Article
Administering increasing dosages of 5alpha-dihydrotestosterone propionate (DHTP) (0, 40, or 80 microgram/100 g in oil daily) to ovariectomized female rats treated concurrently with estradiol benzoate (EB) (1 microgram/100 g in oil daily) caused significant, equivalent reduction in lordotic responsiveness in rats maintained either on a tryptophan-de...
Article
The ability of estradiol benzoate (EB) or EB plus progesterone (P) to induce estrous behavior in the rat is substantially decreased during pregnancy, an effect not solely attributable to high titers of circulating P. The possible contribution of 5α-dihydrotestosterone (DHT) to the inhibition of lordotic responsiveness during pregnancy was studied....
Article
Gonadectomized rats bearing s.c. Silastic capsules containing crystalline oestradiol-17 beta diluted with cholesterol, or oestradiol-17 beta dissolved in sesame oil were tested for the presence of a diurnal rhythm in the display of lordotic behaviour. In experiment 1, female rats received four consecutive tests at intervals of 8 h in a lighting reg...

Citations

... The study of female sexual behavior, particularly their lordosis response, under standard laboratory conditions significantly advanced our knowledge of this behavior. However, interpreting this social affiliative behavior mainly based on lordosis analysis may lead to viewing it as more rigid and passive than it actually is [6,17]. As early as 1976, in his seminal paper on the sexual behavior of female mammals, Frank Beach [5] wrote: ...
... As advocates of the free-market model and laissez faire capitalism, the US and UK under President Ronald Reagan and Prime Minister Margaret Thatcher, respectively, withdrew from UNESCO to show their commitment to neoliberalism (cf. Cowhey, 1990). This political offensive became one of many US strategies during the Cold War period to maintain its global hegemonic position (cf. ...
... Classic studies have shown that when females control or pace the sexual interaction it has positive effects in reproduction, increasing the probability of pregnancy and having a higher number of pups in the offspring compared to females that do not pace the sexual interaction [1,2]. Paced mating also induces a reward state assuring that the behavior will be repeated in the future [3,4]. ...
... Corticosterone, E 2 , P 4 , DHP, and 3α,5α-THP concentrations were measured as described below, using previously reported methods [11,25,38]. Ci/mmol), and 3α,5α-THP (used for DHP and 3α,5α-THP, NET-1047: specific activity = 65.0 ...
... However, the use of the non-hydrolysable ARs agonist R1881 to stimulate isolated SCs from 15-day-old rats showed an increase of LDH A gene expression within 6 h of stimulation [106]. Nevertheless, R1881 does not exactly duplicates the effects of T or DHT [107] and it may exhibit some features that can be called ''side-effects'' [108] thus explaining why the stimulation of R1881 is not able to reproduce the same kind of results of DHT in LDH expression levels. Also, in DHT-treated rat [38] and human [37] cultured SCs, a decrease in alanine and lactate production was reported, suggesting that DHT is responsible for signals that allow SCs to switch their normal glucose metabolism to the Krebs cycle and in this condition cells become metabolically more efficient although lactate production can be compromised (Fig. 3). ...
... Hence, we herewith show for the first time that sexual receptivity of female frogs can be increased by exposure to the nonaromatizable androgen, MDHT, although different exposure concentrations seem to affect female receptivity in opposing ways. Higher doses of MDHT reduce female receptivity potentially by inhibiting estrogen action (DeBold et al., 1978;Erskine et al., 1985, Erskine andMiller, 1995;Falconer et al., 2006) or by interfering with both estrogen and progestin action (Luttge et al., 1977). MDHT might also inhibit estrogenic effects by activating AR and down regulating estrogen receptors (Blasberg et al., 1998;Cárdenas and Pope, 2004). ...
... However, when isolated immature rat SCs were stimulated by the non-hydrolysable ARs agonist R1881, an increase of LDH type A (LDHA) gene expression was reported, immediately after 6 hours [132]. This apparent contradictory results may be explained by the fact that R1881 does not exactly duplicates the effect of T and DHT [133] and may present side effects [134]. Besides controlling lactate metabolism, DHT was also found to decrease acetate production by in vitro cultured human SCs [87]. ...
... Similar effects were obtained after administration of prolactin suggesting that male pheromones mediate prolactin induced neurogenesis in female mice (Larsen and Grattan, 2012;Larsen et al., 2008). To our knowledge, nobody has evaluated the effects of prolactin on adult neurogenesis in the rat, but there is clear evidence indicating that plasma prolactin concentration is increased after mating and this increase is even higher in females that paced the sexual interaction (Erskine, 1989;Erskine and Kornberg, 1992). It is possible then, that sexual behavior increases prolactin levels, which in turn increase neurogenesis in different brain regions. ...
... norepinephrine in ventrolateral areas of ventromedial hypothalamus which promotes pregnancy [11]. In our studies, in the animal group with testicular lesions, where the serotonin content was experimentally increased, and those who received vitamin D 3 on this background, which increases serotonin, sexual behavior disorders persisted. ...
... This, in turn, causes a decrease in the release of LH from the anterior pituitary gland, which is necessary for the activation of Leydig cells to produce testosterone. In addition, opiates were also shown to increase the sensitivity of the hypothalamus to the negative feedback effects of testosterone causing a marked suppression in LH release (Lambert et al., 1990;Hofford et al., 2010;Ruka et al., 2016). Opioidergic transmission reduced, in relation to LHRH release, after long term castration. ...