Article

The Effects of Commercial Preparations of Red Raspberry Leaf on the Contractility of the Rat's Uterus In Vitro

Reproductive Biology Division, Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada.
Reproductive sciences (Thousand Oaks, Calif.) (Impact Factor: 2.18). 03/2010; 17(5):494-501. DOI: 10.1177/1933719109359703
Source: PubMed

ABSTRACT We investigated the direct effects of various commercially available preparations of red raspberry leaf (RRL) on the in vitro contractility of uteri collected from diethylstilbestrol (DES)-treated nonpregnant (NP) and late pregnant rats. In DES-treated NP rats, RRL tea and capsule caused weak contractions. Neither preparation affected the ability of oxytocin to initiate contractions; however, both partially inhibited preexisting oxytocin-driven contractions at the highest concentration tested. Red raspberry leaf ethanol extract had little effect on contractility. Pretreatment with tea did not alter the ability of oxytocin to initiate contractions. In pregnant animals red raspberry leaf tea had variable effects on preexisting oxytocin-induced contractions, sometimes augmenting oxytocin's effect and sometimes causing augmentation followed by inhibition. We conclude that the biological activity of RRL varies depending on the herbal preparation used and pregnancy status. These results do not support the hypothesis that RRL augments labor by a direct effect on uterine contractility.

0 Followers
 · 
92 Views
 · 
0 Downloads
  • [Show abstract] [Hide abstract]
    ABSTRACT: 1. Activation of calcium-sensing receptors (CaS) leads to relaxation of vascular smooth muscle. However, the role of CaS in uterine smooth muscle is unknown. Therefore the aim of the present study was to investigate the expression and function of CaS in the uterus. 2. The expression of CaS in the oestrogen-dominated rat uterus was investigated using immunohistochemistry. The effects of putative CaS ligands on oxytocin-induced contractions of longitudinally orientated uterine strips from oestrogen-dominated rats were determined at reduced extracellular Ca²⁺ concentrations using conventional organ bath techniques. 3. Immunohistochemical evidence showed the presence of CaS in the endometrium and smooth muscle layers of the rat uterus. Oxytocin-induced contractions were inhibited by cations (Gd³⁺ > Ca²⁺ = Mg²⁺), polyamines (spermine > spermidine) and the positive allosteric modulators cinacalcet and calindol. However (R)- and (S)-cinacalcet were equipotent, indicating a lack of stereoselectivity, and the negative allosteric modulator calhex-231 also caused dose-dependent relaxation. In addition, although intermediate-conductance calcium-activated potassium channels and cytochrome P450-dependent signal transduction have been implicated in CaS-induced relaxation of vascular smooth muscle, neither Tram-34 nor miconazole (1 μmol/L), which block these pathways, respectively, had any effect on the ability of cinacalcet to inhibit oxytocin-induced contractions. 4. Calcium-sensing receptors are expressed in smooth muscle layers of the rat uterus and their ligands produce potent relaxation of longitudinally orientated uterine strips. However, the pharmacological profile of inhibition of contractility by CaS ligands is not consistent with a role for CaS in the regulation of uterine contractility in the rat.
    Clinical and Experimental Pharmacology and Physiology 01/2012; 39(1):37-42. DOI:10.1111/j.1440-1681.2011.05631.x · 2.41 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Red raspberry is native to Europe and northern Asia, Russia (eastward to Eastern Siberia) and Central Asia (Tienschan).
    Edible Medicinal And Non-Medicinal Plants, 01/2012: pages 555-569; , ISBN: 978-94-007-4052-5
  • [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Objective: To explore the determinants that are related to women's likelihood to consult with a complementary and alternative medicine (CAM) practitioner during pregnancy. Study setting: Primary data collected as a sub-study of the Australian Longitudinal Study on Women's Health (ALSWH) in 2010. Study design: A cross-sectional survey of 2445 women from the ALSWH 'younger' cohort (n=8012) who had identified as being pregnant or had recently given birth in 2009. Data collection/extraction: Independent Poisson backwards stepwise regression models were applied to four CAM practitioner outcome categories: acupuncturist, chiropractor, massage therapist and naturopath. Principal findings: The survey was completed by 1835 women (79.2%). The factors associated with women's consultation with a CAM practitioner differed by practitioner groups. A range of demographic factors were related, including employment status, financial status and level of education. Women's health insurance coverage, health status, and perceptions toward both conventional maternity care and CAM were also associated with their likelihood of consultations with all practitioner groups but in diverse ways. Conclusions: The determinants for women's consultations with a CAM practitioner varied across practitioner groups. Stakeholders and researchers would benefit from giving attention to specific individual modalities when considering CAM use in maternity care.
    Women & Health 01/2014; 54(2). DOI:10.1080/03630242.2013.876488 · 1.05 Impact Factor