Methods: Flow rates in major vessels and tensions from small pulmonary arteries from the left and right lower lobes were determined
48 hours after creation of an end-to-side anastomosis of the left lower lobe pulmonary artery to the aorta.
Results: Anastomoses increased flow through the left lower lobe pulmonary artery from 194 +/- 6 to 452 +/- 18 mL/min immediately after anastomosis to 756 +/- 19 mL/min by Go6983 ic50 the time of harvest (n = 88, P < .05). Flow rates in main pulmonary arteries from hosts with anastomoses were lower (557 +/- 26 vs 1033 +/- 244 mL/min), whereas aortic root flows were not different from control values (1370 +/- 53 vs 1120 +/- 111 mL/min; P = .07). Wet/dry weights of both lungs and aortic flow rates were proportional to shunt flow rates. Pulmonary artery rings harvested from the right (unshunted) lobes of high-flow hosts exhibited increased reactivity to the thromboxane agonist U46619 and phenylephrine relative to those of left pulmonary arteries from the same animal or those of control hosts.
Conclusions: Our studies are the first to identify enhanced reactivity of pulmonary arteries in a lung contralateral AG-120 to a localized high-output shunt between an aorta and pulmonary artery. These observations suggest that patients with localized systemic-to-pulmonary shunt could exhibit modified vascular tone in remote pulmonary arteries. (J Thorac Cardiovasc Surg 2011;141:407-12)”
of G protein signaling 9-2 (RGS9-2) is a constituent of G protein-coupled receptor (GPCR) macromolecular complexes with a major role in regulation of GPCR activity in the central nervous system. Previous in situ hybridization and Western blot studies revealed that RGS9-2 is expressed in the superficial dorsal horn of the spinal cord. In the present study, we monitored
tail withdrawal latencies to noxious thermal stimuli and performed in vitro whole-cell patch clamp electrophysiological recordings from neurons in lamina II of the spinal dorsal horn to examine the role of RGS9-2 in the dorsal horn of the spinal cord in nociceptive behaviours and opiate mediated modulation of synaptic transmission. Our findings obtained AZD9291 datasheet from RGS9 knockout mice indicate that the lack of RGS9-2 protein decreases sensitivity to thermal stimuli and to the analgesic actions of morphine in the tail immersion paradigm. This modulatory role of RGS9-2 on opiate-mediated responses was further supported by electrophysiological studies showing that hyperpolarization of neurons in lamina II of the spinal dorsal horn evoked by application of DAMGO ([D-Ala2, N-MePhe4, Gly-ol]-enkephalin, a mu opioid receptor agonist) was diminished in RGS9 knockout mice. The results indicate that RGS9-2 enhances the effect of morphine and may play a crucial role in opiate-mediated analgesic mechanisms at the level of the spinal cord. (C) 2011 Elsevier Ireland Ltd. All rights reserved.