تحریک الکتریکی هسته دسته منزوی ، حساسیت بارورفلکس را در رت های معتاد به مورفین افزایش می دهد

The previous studies have shown that the endogenous opiate system depress&nbsp;the baroreflex sensitivity in morphine dependent persons. Nucleus Tractus&nbsp;Soloitarii(NTS) is the main termination site of baroreceptor afferent neurons. The aim&nbsp;of this study was to determine the role of electrical stimulation of Nucleus Tractus &nbsp;&nbsp; Soloitarii on baroreflex sensitivity in morphine-addicted rats. Male Wistar rats were addicted during scheduled 10 days with morphine&nbsp;sulphate(i.p.) and anesthetized by Urethane(150mg/100gr body weight i.v.) then&nbsp;cannulated with PE50 tubes filled with Saline/heparin (200u/ml) &nbsp;in femoral artery&nbsp;and vein for recording mean arterial pressure (MAP) and heart rate (HR) &nbsp;&nbsp; respectively. The electrodes were implanted in NTS, &nbsp;according Paxinous atlas in&nbsp;streotaxic instruments for applying electrical stimulation. Phenylepherine was used&nbsp;as a vasoconstrictor to induce acute arterial pressure. Baroreflex sensitivity was&nbsp;evaluated (&Delta;HR/&Delta;MAP) before and after electrical stimulation application in NTS.&nbsp;Control group was received saline instead of morphine. The results showed that baroreflex sensitivity decreased in morphine addicted&nbsp;rats compared to control. There was no significant changes in mean arterial&nbsp;pressure and HR&nbsp;after electrical stimulation application in NTS in both morphine&nbsp;and control groups, but baroreflex sensitivity&nbsp;increased after application of&nbsp;electrical stimulation in NTS in morphine addicted rats(P<0.05). It is suggested that application of electrical stimulation in NTS can modulate&nbsp;neurotransmission in central nervous system such as GABAergic function, therefore&nbsp;this modulation may prevent some abnormality in cardiovascular area in addicted&nbsp;rats.