Letter to neuroscienceOrexin A (hypocretin-1) application at the medial preoptic area potentiates male sexual behavior in rats
Section snippets
Experimental procedures
The study was conducted on ten adult male Wistar rats, weighing 180–250 g. The animals were kept in controlled temperature (25±2 °C) under 14:10h light-dark schedule (light on at 6:00 A.M.). Food and water were provided ad libitum. The rats were screened for sexual behavior using standard criteria Mittimohan et al 1989, Mallick et al 1996 and those having a sex drive score above four were chosen for the study. Under sodium pentobarbital anesthesia (40 mg/kg body wt, i.p.), 26 gauge bilateral
Results and discussion
Seven rats in which OX-A was bilaterally injected at the mPOA were grouped together for statistical analysis. The bilateral microinjection of OX-A (0.3 nmol) in the mPOA (n=7) produced significant decrease in latencies to mount, intromission and ejaculation (Table 1). There was significant decrease in post-ejaculatory interval and mean inter-intromission interval (P<0.05) and increase in pursuit, mount, intromission frequencies (P<0.05) and sex drive scores (P<0.05). The OX-A treated rats were
Acknowledgements
Statistical help rendered by Dr. K. R. Sundaram, Department of Biostatistics, All India Institute of Medical Sciences, is acknowledged.
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