en فارماكولوژی و سم شناسی Pharmacology & Toxicology پژوهشی Research <div style="text-align: justify;"><b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times=""><span style="color:black">Background:</span></span></span></b> <i><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">Dracocephalum kotschyi</span></span></i><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times=""> is a medicinal plant with well-documented anti-spasmodic and anti-inflammatory properties. However, its potential effects on blood pressure have not been previously investigated. <b>Objective:</b> This study aimed to evaluate the pharmacological effects of <i>D. kotschyi</i> essential oils and its hydroalcoholic extract on blood pressure in rats. <b>Methods: </b>Male Wistar rats were divided into four groups (n = 6/group): vehicle, Nifedipine, <i>D. kotschyi</i> hydroalcoholic extract, and <i>D. kotschyi</i> essential oil. The hydroalcoholic extract and essential oil were prepared by maceration and hydrodistillation, respectively. Under anesthesia, the jugular vein and carotid artery were cannulated, and the carotid cannula was connected to a pressure transducer for continuous blood pressure recording. The effects of intravenous administration of the vehicle, Nifedipine (50-500 &micro;g/kg), the hydroalcoholic extract (20-200 mg/kg), and the essential oil (2-20 mg/kg) on blood pressure were assessed. </span></span><b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">Results: </span></span></b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">Intravenous administration of <i>D. kotschyi</i> essential oil significantly reduced blood pressure at 8 mg/kg (P < 0.05) and at 12 and 20 mg/kg (P < 0.01) compared with the vehicle-treated group. In contrast, the hydroalcoholic extract did not significantly affect blood pressure at any of the tested dose. As expected, Nifedipine significantly reduced blood pressure compared with the vehicle-treated group (P < 0.01). </span></span><b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">Conclusion: </span></span></b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">The <i>D. kotschyi</i> essential oil contains vasoactive constituents capable of lowering blood pressure. Conversely, the inactivity of the hydroalcoholic extract suggests that its volatile hypotensive constituents were largely lost during rotary evaporation.</span></span></div> Cardiovascular, Hypotension, Plant Extraction, Zaringiah, Dracocephalum kotschyi. 65 77 http://jmp.ir/browse.php?a_code=A-10-7111-1&slc_lang=en&sid=1 Mina Sadat Izadi minna.izadi@gmail.com 100319475328460050173 100319475328460050173 No Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran Zahra Karami Zahra.karami@gmail.com 100319475328460050174 100319475328460050174 No Department of Pharmacology and Toxicology, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran Afsaneh Yegdaneh yekdaneh@pharm.mui.ac.ir 100319475328460050175 100319475328460050175 No Department of Pharmacognosy, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran Hassan Sadraei sadraei@pharm.mui.ac.ir 100319475328460050176 100319475328460050176 Yes Department of Pharmacology and Toxicology, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran