Argiolas A, Melis M R, Stancampiano R, Gessa G L
B.B. Brodie Department of Neurosciences, University of Cagliari, Italy.
Pharmacol Biochem Behav. 1990 Oct;37(2):253-7. doi: 10.1016/0091-3057(90)90330-k.
The effect of the intracerebroventricular (ICV) administration of omega-conotoxin GVIA on penile erection and yawning induced by oxytocin or by the dopaminergic agonist apomorphine was studied in male rats. The peptide toxin, 1-10 ng given ICV 5 min before oxytocin (30 ng ICV) or apomorphine (80 micrograms/kg SC), but not its carboxymethylated (CM) derivative, prevented the above behavioral responses in a dose-dependent manner. Similarly, omega-conotoxin (5 ng) unilaterally injected in the paraventricular nucleus of the hypothalamus (PVN) prevented penile erection and yawning induced by the microinjection of oxytocin (10 ng) or apomorphine (50 ng) in the PVN. omega-Conotoxin injected in the PVN, but not in the preoptic area, prevented also penile erection and yawning induced by systemic apomorphine (80 micrograms/kg SC). ICV omega-conotoxin was unable to prevent stereotypy induced by apomorphine (500 micrograms/kg SC). The present results provide further evidence that calcium plays a major role in the expression of penile erection and yawning and that apomorphine and oxytocin induce these behavioral responses by mobilizing calcium through omega-conotoxin-sensitive (N-type) calcium channels.
研究了在雄性大鼠中，脑室内（ICV）注射ω-芋螺毒素GVIA对由催产素或多巴胺能激动剂阿扑吗啡诱导的阴茎勃起和打哈欠的影响。在催产素（30 ng ICV）或阿扑吗啡（80 μg/kg皮下注射）前5分钟，脑室内注射1 - 10 ng的肽毒素可剂量依赖性地阻止上述行为反应，但其羧甲基化（CM）衍生物则无此作用。同样，在下丘脑室旁核（PVN）单侧注射ω-芋螺毒素（5 ng）可阻止由在PVN微量注射催产素（10 ng）或阿扑吗啡（50 ng）所诱导的阴茎勃起和打哈欠。注射在PVN而非视前区的ω-芋螺毒素，也可阻止由全身注射阿扑吗啡（80 μg/kg皮下注射）所诱导的阴茎勃起和打哈欠。脑室内注射ω-芋螺毒素不能阻止由阿扑吗啡（500 μg/kg皮下注射）诱导的刻板行为。目前的结果进一步证明，钙在阴茎勃起和打哈欠的表现中起主要作用，且阿扑吗啡和催产素通过ω-芋螺毒素敏感的（N型）钙通道动员钙来诱导这些行为反应。
