Autonomic effects induced by pharmacological activation and inhibition of Raphe Pallidus neurons in anaesthetized adult pigs.

Autonomic effects induced by pharmacological activation and inhibition of Raphe Pallidus neurons in anaesthetized adult pigs. Clin Exp Pharmacol Physiol. 2019 Oct 18;: Authors: Zucchelli M, Bastianini S, Ventrella D, Barone F, Elmi A, Romagnoli N, Hitrec T, Berteotti C, Di Cristoforo A, Luppi M, Amici R, Bacci ML, Cerri M Abstract The Raphe Pallidus (RPa) is a region of the brainstem that was shown to modulate the sympathetic outflow to many tissues and organs involved in thermoregulation and energy expenditure. In rodents, the pharmacological activation of RPa neurons was shown to increase the activity of the brown adipose tissue, heart rate, and expired CO2 , whereas their inhibition was shown to induce cutaneous vasodilation and a state of hypothermia that, when prolonged, leads to a state resembling torpor referred to as synthetic torpor. If translatable to humans, this synthetic torpor-inducing procedure would be advantageous in many clinical settings. A first step to explore such translatability, has been to verify whether the neurons within the RPa play the same role described for rodents in a larger mammal such as the pig. In the present study, we show that the physiological responses inducible by the pharmacological stimulation of RPa neurons are very similar to those observed in rodents. Injection of the GABAA agonist GABAzine in the RPa induced an increase in heart rate (from 99 to 174 bpm), systolic (from 87 to 170 mmHg) ...
Source: Clinical and Experimental Pharmacology and Physiology - Category: Drugs & Pharmacology Authors: Tags: Clin Exp Pharmacol Physiol Source Type: research