These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Sex differences in cardiac muscle responsiveness to Ca2+ and L-type Ca2+ channel modulation.
    Author: Curl CL, Delbridge LM, Wendt IR.
    Journal: Eur J Pharmacol; 2008 May 31; 586(1-3):288-92. PubMed ID: 18371950.
    Abstract:
    This study investigated sex-related differences in rat papillary muscle force generation in response to altered extracellular [Ca2+] ([Ca2+](o), 0.2 to 5.0 mM) and to L-type Ca2+ channel modulators (nifedipine and Bay K8644). At all [Ca2+]o examined, contractile force was significantly greater in male than female papillary muscles. The [Ca2+]o required for 50% maximum force was significantly lower in male [0.34+/-0.06 mM] than female [0.61+/-0.10 mM] papillary muscles. Nifedipine decreased contractile force in papillary muscles of both sexes in a concentration-dependent manner, but the extent of the contractile depression was more marked in male papillary muscles at all nifedipine concentrations examined. BayK 8644 produced a concentration-dependent increase in contractile force in male papillary muscles but notably, not in female papillary muscles. These findings show that sex differences in myocardial mechanical function are associated with sex-specific modulation of L-type Ca2+ channel responsiveness. Thus, the L-type Ca2+ channel could represent an important cellular locus from which sex-based differences in myocardial excitation-contraction coupling arise.
    [Abstract] [Full Text] [Related] [New Search]