E Ruiz

Hospital Universitario San Cecilio, Granata, Andalusia, Spain

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Publications (40)53.27 Total impact

  • Hormone and Metabolic Research 05/2008; 40(4):289-91. · 2.15 Impact Factor
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    ABSTRACT: The development and growth of the prostate gland depends on androgen stimulation. Dihydrotestosterone (DHT) is the primary androgen responsible for prostate development and also for the pathogenesis of benign prostatic hyperplasia (BPH). The incidence of prostate cancer (PCa) and benign prostatic hypertrophy (BPH) continues to rise in the Western world. DHT is synthesized in prostate from circulating testosterone (T) through the action of 5alpha-Reductase (5alpha-R) (EC 1.3.99.5), which occurs as two isozymes, type 1 and type 2. Type-1 5alpha-R is widely distributed in the body, and type-2 5alpha-R is confined to androgen-dependent structures. Both types are expressed in the prostate: type-2 isozyme is implicated in BPH and PCa; type-1 isozyme is also increased in some prostatic adenocarcinomas. In recent years, various inhibitors of type-2 isozyme or of both type-1 and type-2 isozyme have been used in prostatic diseases. In this work we present measurements of mRNA levels of steroid 5alpha-R isozymes in the ventral prostate of rats of different androgen status. We used a novel method that combines the high specificity of semiquantitive PCR with the sensitivity of laser-induced fluorescence capillary electrophoresis (LIF-CE). We demonstrated that T control the expression of 5alpha-R2 isozyme in rat prostrate. This approach could be of great value for the study of prostate diseases in humans and would allow study at the transcriptional level the effects of drugs that inhibit either or both of these isozymes.
    Molecular and Cellular Biochemistry 09/2003; 250(1-2):125-30. · 2.33 Impact Factor
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    ABSTRACT: The incidence of prostate cancer (PCa) and benign prostatic hypertrophy (BPH) continues to rise in the Western world. The development and growth of the prostate gland depends on androgen stimulation. Dihydrotestosterone (DHT) is the primary androgen responsible for prostate development and also for the pathogenesis of benign prostatic hyperplasia (BPH). DHT is synthesized in prostate from circulating testosterone (T) through the action of 5alpha-Reductase (5alpha-R) (EC 1.3.99.5), which occurs as two isozymes, type-1 and type-2. Both types are expressed in the prostate: type-2 isozyme is predominantly expressed in prostate and is implicated in BPH and PCa; type-1 isozyme is also increased in some prostatic adenocarcinomas. In recent years, various inhibitors of type-2 isozyme or of both type-1 and type-2 isozyme have been used in prostatic diseases. We present the first published measurements of mRNA levels of steroid 5alpha-R isozymes in the ventral prostate of rats of different androgen status. We used a novel method that combines the high specificity of competitive PCR with the sensitivity of laser-induced capillary electrophoresis (LIF-CE). We demonstrated that T and DHT androgens control the expression of both 5alpha-R isozymes in rat prostrate. This approach could be of great value for the study of prostate diseases in humans and would allow study at the transcriptional level of the effects of drugs that inhibit either or both of these isozymes.
    The Prostate 07/2003; 56(1):74-9. · 3.84 Impact Factor
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    J M Torres, E Ruiz, E Ortega
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    ABSTRACT: The 3alpha-hydroxy ring A-reduced metabolite of progesterone, 3alpha-hydroxy-5alpha-pregnan-20-one (allopregnanolone) is among the most potent known ligands of the gamma aminobutyric acid (GABA) receptor, designated GABA-A, in the central nervous system. We determined by RIA serum levels of progesterone (PROG), 5-alpha-dihidroprogesterone (DHP) and allopregnanolone in male and female rats after corticotropin releasing hormone (CRH) and adrenocorticotropin hormone (ACTH) administration. Allopregnanolone was undetectable in plasma and brain of control males but detectable in plasma and brain of males injected with CRH and ACTH and of control and similarly treated females. Allopregnanolone increased in the plasma and brain after CRH and ACTH administration in all cases. The data demonstrate that the administration of CRH plus ACTH results in a rapid increase of the neuroactive steroid allopregnanolone in the brain of males and females to levels known to modulate GABA-A receptor function. Thus, stress could regulate neurosteroid biosynthesis via the hormones ACTH and CRH.
    Neurochemical Research 06/2001; 26(5):555-8. · 2.13 Impact Factor
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    ABSTRACT: Previous investigations in our laboratory have shown that testosterone implanted into the lateral septum in male rats increases LH and FSH secretion. However, it was unclear whether the effect of testosterone was direct via androgen receptor, or indirect via the estrogen receptor after conversion by aromatization to estradiol. To answer this question, we implanted either testosterone or the non-aromatizable androgen 5 alpha-dihydrotestosterone (DHT), into the lateral septum of adult male rats and measured plasma levels of LH and FSH by radioimmunoassay 2 days after implantation. Both testosterone and DHT significantly increased the plasma LH and FSH concentrations. Mean concentration of LH in control animals was 0.21 +/- 0.06 ng/ml, a figure that increased to 0.7 +/- 0.12 and 0.55 +/- 0.1 ng/ml after DHT or testosterone implantation respectively. Mean concentration of FSH in control animals was 1.5 +/- 0.3 ng/ml; this figure increased to 3 +/- 0.3 and 2.9 +/- 0.3 ng/ml after DHT or testosterone implantation. Neither plasma DHT (64.0 +/- 5.6 vs. 52 +/- 5 ng/100ml) nor plasma testosterone levels (4.1 +/- 0.38 vs. 3.3 +/- 0.18 ng/ml) were significantly affected by the implants. We conclude that androgens independently of conversion to estrogen acting in the lateral septum facilitates the release of LH and FSH.
    Endocrine Research 01/2001; 27(1-2):35-40. · 1.03 Impact Factor
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    ABSTRACT: To study the possible role of sexual hormones, Testosterone (T), Estradiol (E2), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) on the growth axis, we examined the correlations between the sex, growth hormone (GH), insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein 3 (IGFBP3), FSH, LH, T and E2, in growth retarded children ranging in age from 7 to 13 yr. All hormones were measured by Radioimmunoassay (RIA) in a pool of aliquots of samples obtained every 20 min over 12 h (overnight) in each child. Multivariate statistical analysis was performed. We have found: a) Thai only FSH concentrations were significantly higher in girls than in boys; b) A positive correlation between T-IGF-1; T-IGFBP3; FSH-LH; FSH-IGF-1; FSH-IGFBP3, LH-IGF-1, LH-IGFBP3 the sex-FSH; and the sex-IGFBP3 c) A high positive correlation between plasmatic E2 and IGF-1/IGFBP3 ratio (an index of free, active IGF-1). We concluded that the sex, FSH, LH, T and E2 influence the growth axis. The sex through IGFBP3; LH, FSH, and T through IGF1 and IGFBP3; E2 through the IGF-1/IGFBP3 ratio, an index of active IGF-1.
    Endocrine Research 01/2001; 27(1-2):25-33. · 1.03 Impact Factor
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    ABSTRACT: We previously reported the deleterious effects of acute alcohol intoxication (AAI) on pituitary-gonadal and pituitary-adrenal axes hormones in human adolescents. In the present paper we studied the effects of AAI on the growth axis hormones, and the possible contribution of the insulin-glucose axis to the alcohol-induced dysfunction of the growth axis in human adolescents. Blood samples were drawn from adolescents that arrived at the emergency department with evident behavioural symptoms of drunkenness (AAI) or with nil consumption of alcohol (controls [C]). AAI produced in the adolescents of both sexes in our series: a decrease in growth hormone (GH) levels, without significant alteration of either insulin-like growth factor-I (IGF-I) or insulin-like growth factor binding protein-3 (IGFBP3); an increase in plasma glucose and a decrease in insulin in the female adolescents but not in the males. Males and females undergo a significant period of bone growth during adolescence. Growth axis hormones play an important role in the pubertal spurt. Thus, ethanol consumption during adolescence could have long-lasting deleterious effects on this aspect of development. In industrialised countries, around 35% of alcohol drinkers are under 16 years old, therefore the result of this study should be made known to adolescents and the appropriate authorities.
    Life Sciences 11/2000; 67(22):2691-7. · 2.56 Impact Factor
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    ABSTRACT: Serum levels of cholesterol (Chol), triglycerides (TG), low-density lipoprotein cholesterol (LDL) high-density lipoprotein cholesterol (HDL), both apolipoproteins A1 and B (Apo A1, Apo B), follicle-stimulating hormone (FSH) luteinizing hormone (LH), estradiol (E2), progesterone (P), testosterone (T) and steroid hormone binding globulin (SHBG) were measured in postmenopausal women, before and after four different estrogen-progestin replacement therapies. Each woman was her own control to avoid genetic or socioeconomic differences. Our results showed that serum E2 and TG significantly increased and serum FSH, LH, LDH, Apo B, and Chol significantly decreased after all treatments. Serum P and T did not significantly change after any of the treatments. HDL, Apo A1 and SHBG significantly increased in the groups treated with medroxiprogesterone acetate (MPA) but not in the group treated with Norgestrel. We conclude that estrogen-progestin replacement therapy in postmenopausal women leads to profound and beneficial changes in plasma lipids and lipoproteins and that treatments with cyclic or continuous MPA could provide greater protection against coronary heart disease (CHD).
    Endocrine Research 06/2000; 26(2):263-73. · 1.03 Impact Factor
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    ABSTRACT: Teenage drinking continues to be a major problem in industrialized countries, where almost 35% of alcohol drinkers are under 16 years old. In the present paper we studied the effects of acute alcohol intoxication (AAI) on the pituitary-gonadal (PG) axis hormones, and the possible contribution of pituitary-adrenal (PA) axis hormones, beta-endorphin (BEND), and prolactin (PRL) to the alcohol-induced dysfunction of PG axis hormones. Blood samples were drawn from adolescents that arrived at the emergency department with evident behavioral symptoms of drunkenness (AAI) or with nil consumption of alcohol (controls [C]). Our results demonstrated that AAI produces in adolescents a high increase in plasma PRL, ACTH, and cortisol (F), and a contradictory behavior of testosterone (T) according to gender: plasma T was increased in females and decreased in males. ACTH and PRL correlated positively with F, dehydroepiandrosterone-sulphate (DHEAS) and T in females, which suggests that PRL and ACTH could synergistically stimulate adrenal androgen production. In contrast, the decrease in T and increase in BEND in males suggests that AAI could have an inhibitory effect on testicular T, perhaps mediated by BEND. The hormones studied are involved in the development of secondary sexual characteristics and the growth axis during adolescence. The deleterious effects of alcohol abuse should be made known to adolescents and the appropriate authorities.
    Life Sciences 02/2000; 67(9):1081-6. · 2.56 Impact Factor
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    J Frias, E Ruiz, E Ortega
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    ABSTRACT: We determined the dose-response relationship and examined the time-related effect of CRF (corticotropin releasing factor) injected directly into the Median Eminence (ME) on GH (growth hormone) secretion in conscious intact and castrated male rats. Doses of 0.25, 0.75, 1, and 1.5 nmol CRF dissolved in 1 microl of saline, or saline alone in the controls, were injected into the ME, and blood samples collected through indwelling catheters implanted in the jugular vein, 30, 60, 90, and 120 min post-injection to determine plasma GH levels by RIA. After 120 min the animals were decapitated. Trunk blood of decapitated animals was used to determine plasma testosterone and glucose levels. CRF at all the doses studied significantly decreased plasma GH in castrated and intact animals. The results suggest that in male as in female rats, CRF inhibits by itself GH secretion, at least in part, by a central action in the ME; all the doses of CRF studied suppressed GH secretion in castrated and intact males; finally, CRF at ME levels may participate in a variety of stress-related responses, including growth inhibition, through GH suppression.
    Neurochemical Research 07/1999; 24(6):715-8. · 2.13 Impact Factor
  • A Osorio, E Ruiz, E Ortega
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    ABSTRACT: We have monitored estrous cycle and measured serum estradiol, GH, IGF-1, T4 and T3 levels in adult hypothyroid female rats which were divided into four groups: H group, hypothyroid rats without treatment; H-T4 group, hypothyroid rats injected daily with T4; HT4-PTU group, hypothyroid rats injected daily with T4 plus PTU (propylthiouracil), and H-T4-IOP group, hypothyroid rats injected daily with T4 plus IOP (iopanoic acid); Euthyroid rats (E group) were used as control. Our results indicate that the lack of sexual cycle in H animals was associated with lower values of estradiol, GH and IGF-1 in comparison to E group; the restoration of sexual cycle in H-T4 group was associated with values of estradiol, GH and IGF-1 higher than those of H group, whereas in H-T4-PTU and H-T-IOP groups the restoration was associated with higher values of GH and IGF-1 and values of estradiol similar to those of H group. These data could suggest a potential role of GH/IGF-1 axis, at least in part, in the lack of sexual cycle in H group and in the ovulation induction in H-T4, H-T4-PTU and H-T4-IOP groups.
    Molecular and Cellular Biochemistry 02/1998; 179(1-2):7-11. · 2.33 Impact Factor
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    ABSTRACT: We determined the dose-response relationship and examined the time-related effect of CRF (corticotropin releasing factor) injected directly into the Median Eminence (ME) on LH secretion in conscious intact and castrated male rats. Doses of 0.25, 0.75, 1, and 1.5 nmol CRF dissolved in 1 microl of saline (or saline only in the controls) were injected into the ME and blood samples collected 30, 60, 90, and 120 min postinjection to determine by RIA serum LH. CRF at doses of 0.75, 1 and 1.5 nmol significantly decreased serum LH in castrated and intact animals. The lower dose of CRF did not decrease LH in the two groups studied. The results suggest that in males as in females, CRF inhibits by itself LH secretion, at least in part, by a central action in the ME; the inhibitory effect of CRF on LH is similar in castrated and intact males; the dose of 0.25 nmoles of CRF was ineffective in decreasing LH and finally that CRF at ME levels may participate in a variety of stress-related responses, including reproduction inhibition, through LH suppression.
    Neurochemical Research 03/1997; 22(2):171-4. · 2.13 Impact Factor
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    ABSTRACT: To evaluate whether the median eminence (ME) is a site of action of CRF (corticotropin releasing factor) on GH secretion and to determine the possible role of estradiol and progesterone in modifying theses secretion, we injected CRF (0.25, 0.75, 1, and 1.5 nmol of peptide dissolved in 1 microliter of water) directly into the ME in three experimental groups of rats: Long-term ovariectomized (OVX); OVX primed by estradiol (OVX +/- E) and OVX primed by estradiol plus progesterone (OVX +/- EP). Blood was collected to determine GH (30, 60, 90, and 120 min postinjection). Serum T3, T4, and glucose levels were measured in OVX +/- E rats 30 min postinjection. CRF at all doses studied significantly decreased serum GH levels in the three experimental groups. Serum T3, T4, and glucose levels were unchanged after CRF administration. The results suggest that: CRF inhibits "per se" GH secretion, at least in part, by a central action in the ME. The inhibitory effect of CRF on GH is independent of the estrogen/progesterone status of the animal. CRF at ME levels may participate in a variety of stress-related responses, including growth inhibition, through GH suppression.
    Neurochemical Research 09/1996; 21(8):897-901. · 2.13 Impact Factor
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    E Ortega, A Osorio, E Ruiz
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    ABSTRACT: Hypothyroid female rats were treated with T4 and their 5'DI and 5'DII deiodinases were inhibited by PTU and IOP administration to determine whether the effect of T3 on reproductive function is a primary event at hypothalamo-pituitary levels or ovarian levels. Hypothyroid adult female rats were divided into four groups: Hypothyroid without treatment (H); hypothyroid treated with T4 (H-T4); hypothyroid treated with T4 plus propylthiouracil (H-T4-PTU), and hypothyroid treated with T4 plus iopanoic acid (H-T4-IOP). A group of euthyroid rats (E) was included as control. Estrous cycle, ovarian histological changes and serum estradiol and gonadotropin levels (basal and after GnRH) were searched in all groups. In view of our results and since sexual cycles and puberal pattern in gonadotropin secretion were restored after all treatments we can suggest: That T4 could have an intrinsic effect on reproductive function in adult hypothyroid female rats or that another compensatory T3 mechanism unaffected by IOP could exist. The present report points out that the effect of T3 on reproductive function could be a primary event at hypothalamopituitary levels although an effect at ovarian levels could not be excluded.
    Biochemistry and molecular biology international 08/1996; 39(4):853-60.
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    ABSTRACT: The effect of zinc on reproductive function was studied in rats fed with a zinc-deficient diet and control rats fed with a standard diet.Serum testosterone (T) levels were measured before and after the injection of HCG (human chorionic gonadotropin). Serum gonadotrophin levels were measured before and after the injection of GnRH (gonadotropin releasing hormone). In addition, structural parameters were studied and morphometric techniques were used to study the seminiferous tubules. The findings were used to investigate the possible relationship between biochemical and morphometric changes. Body weight (BW) gain, zinc content of testes and weight of the testes, seminal vesicle, and prostate were significantly lower in zinc-deficient rats compared with controls. Serum zinc concentrations and alkaline phosphatase activity were decreased in zinc-deficient rats compared with controls. Serum basal and stimulated FSH concentrations were similar in the two groups. Serum LH response to GnRH was higher in zinc-deficient rats. Serum basal T was lower in zinc deficient animals, but the response of T to HCG was similar in the two groups. The basal and luminal diameters, perimeter, and surface area of the seminiferous tubules as well as tubule volume, wall thickness, and cross-section area decreased in zinc-deficient animals in comparison with controls. Concentrations of zinc were significantly correlated with structural parameters and serum T levels. The changes in T levels correlated positively with the structural parameters and morphological findings.
    The Journal of Nutritional Biochemistry 01/1996; · 4.55 Impact Factor
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    ABSTRACT: We determined the dose-response relationship and examined the time related effect of CRF (corticotropin releasing factor) injected directly into the median eminence (ME) on LH and FSH secretion in conscious female rats of different steroid status. Doses of 0.25, 0.75, 1, and 1.5 nM CRF dissolved in 1 microliter of water were injected into the ME in 5 experimental groups of rats: Short-term (2 days) ovariectomized (sOVX); long-term (3-4 weeks) ovariectomized (lOVX); lOVX primed by estradiol benzoate (EB) 4 h before the experiment (lOVX+E); lOVX primed by EB 36 h before the experiment (lOVXE) and lOVX primed by EB 72 h and progesterone 6 h before experiment (lOVXP). Blood was collected at 30, 60, 90, and 120 min postinjection to determine LH and FSH by RIA. CRF at the doses of 0.75, 1, and 1.5 nM significantly decreased serum LH levels in all groups. The dose of 0.25 nM CRF was ineffective. The highest dose (1.5 nM) of CRF had no effect on serum FSH levels. The results suggest that CRF inhibits LH secretion, at least in part, by a central action of GnRH release in the ME, and that this effect is independent of the estrogen/progesterone status of the animal.
    Neurochemical Research 11/1994; 19(10):1225-30. · 2.13 Impact Factor
  • E Ruiz, E Osorio, E Ortega
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    ABSTRACT: To evaluate whether the median eminence (ME) is a site of action of opioids on gonadotropin secretion, we injected naloxone into the ME in male rats and measured LH and FSH serum levels. Injection into the ME of either 0.5 or 1 microgram of naloxone significantly decreased serum LH levels 10 and 30 min postinjection. A dose of 0.1 microgram had not effect. Naloxone at the doses used had no significant effect on FSH secretion. From these data it can be concluded that endogenous opioids exert a tonic stimulation on LH secretion under our experimental conditions.
    Biochemistry and molecular biology international 01/1994; 31(5):889-95.
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    ABSTRACT: To evaluate whether the median eminence (ME) is a site of action of opioids on gonadotropin secretion, and to determinate the role of estradiol (E) and progesterone (P) in modifying these secretion in response to naloxone, we injected naloxone (1, 2.5 and 5 micrograms) into the ME in ovariectomized rats treated with estradiol benzoate (OVX+E) or ovariectomized rats treated with estradiol benzoate plus progesterone (OVX+E+P), and measured LH and FSH serum levels 10 and 30 min postinjection. Naloxone injection at doses of 2.5 and 5 micrograms significantly increased serum LH levels in OVX+E animals 10 and 30 min postinjection, whereas naloxone injection at all doses in OVX+E+P rats did not have any significant effect on LH secretion 10 and 30 min postinjection, when compared with values obtained in controls injected with saline. The injection of naloxone into the ME did not modify FSH secretion. We conclude that naloxone, acting within the ME, can elicit LH release in OVX+E rats, while it abolishes this effect in OVX+E+P rats.
    Biochemistry and molecular biology international 09/1993; 30(6):1093-100.
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    ABSTRACT: Serum beta-endorphin, LH, FSH, estradiol (E2) and progesterone (P) were measured in postmenopausal women before and after four different estrogen-progestin replacement therapies. Our result showed that serum E2 increased significantly and serum LH and FSH decreased significantly after all treatments. Serum P levels were similar before and after all treatments. Serum beta-endorphin levels increased significantly after cyclic administration of estrogen-progestin, but not after continuous administration of E2. We conclude that the frequently observed beneficial effects of estrogen-progestin replacement therapy on behavior and mood in postmenopausal women may be related to changes in peripheral opioid levels.
    Biochemistry and molecular biology international 05/1993; 29(5):831-6.
  • E Ruiz, E Osorio, E Ortega
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    ABSTRACT: Serum total testosterone (T), free testosterone (fT) sex hormone binding globulin (SHBG), androstenedione (A) and 3 alpha androstanediol glucuronide (3 alpha-diol G) levels as well as serum free androgen index (FAI), fT/T and 3 alpha-diol G/T ratios were measured in premenopausal and cyclic women, grouped according to sexual status and smoking status. Our results showed that serum T, fT, SHBG, A and 3 alpha-diol G levels were lower in cyclic women in the follicular than in the luteal phase of the ovarian cycle, although the differences between these values were not significant. Postmenopausal women had significantly lower values of T, fT, A 3 alpha-diol G, FAI and 3 alpha diolG/T but not SHBG and fT/T than cyclic women. When we compared women smokers and nonsmokers, women smokers had serum levels of T, fT, SHBG, 3 alpha-diol G, and values of FAI, fT/T and 3 alpha-diol G/T, similar to those in nonsmokers. Serum A levels were higher in women smokers than in nonsmokers, although the difference was significant only in postmenopausal women.
    Biochemistry international 09/1992; 27(5):841-5.

Publication Stats

272 Citations
53.27 Total Impact Points

Institutions

  • 2000–2001
    • Hospital Universitario San Cecilio
      • Clinical Biochemistry Unit
      Granata, Andalusia, Spain
  • 1984–2001
    • University of Granada
      • • Departamento de Bioquímica y Biología Molecular
      • • Facultad de Medicina
      Granada, Andalusia, Spain
  • 1987–1990
    • Facultad de Medicina
      Madrid, Madrid, Spain