[Role of cyclic nucleotides in formation of pathologic reactions in the immediate postoperative period]. / Rol' tsiklicheskikh nukleotidov v formirovanii patologicheskikh reaktsii v blizhaishem posleoperatsionnom periode.

Effects of anesthesia and surgery on the level of cyclic nucleotides (CN) and their role in the formation of pathological reactions are little studied. We measured plasma concentrations of CN for evaluating the quantitative and qualitative changes in adenylate-guanylate cyclase metabolism under the effect of operation and for elucidating the role of these changes in postoperative disorders of hemodynamics and gas exchange. The findings in patients with surgical diseases of the lungs (168 pts), with acquired and congenital heart diseases (193 pts), and with atherosclerotic involvement of the aorta (63 pts) were analyzed. The CN system is responsible for the pre-, intra-, and postoperative status of surgical patients, which manifests by a hypermetabolic reaction leading to an increase in the blood concentrations of cAMP and cGMP. At the initial stages this reaction is compensatory, while in the immediate postoperative period CN are involved in the pathological mechanisms leading to hemodynamic disorders.

[Role of neuropeptides and "pain substances" in the formation of humoral mechanisms of experimental and postoperative pain]. / Rol' neiropeptidov i "bolevykh substantsii" v formirovanii gumoral'nykh mekhanizmov éksperimental'noi i posleoperatsionnoi boli.

Humoral mechanisms of pain caused by different factors vary. The authors compare blood concentrations of "painful substances" in experimental dogs and in patients suffering from postoperative pain relieved by electroacupuncture for assessing the role of these substances: serotonin, histamine, prostaglandin F2 alpha (PGF), and neuropeptides beta-endorphine, methionine- and leucine-enkephalines. Serotonin, histamine, and PGF participated in the nociception process in an equal measure both in dogs and humans. Notable differences were observed for neuropeptides, which can be explained by species-specific differences and by probable contribution of other neuropeptides to mechanisms of experimental and postoperative pain.

[Changes in the concentration of endogenous opiates in the blood and cerebrospinal fluid during acute painful stimuli and protective electroacupuncture analgesia]. / Izmeneniia kontsentratsii éndogennykh opiatov v plazme krovi i spinnomozgovoi zhidkosti pri ostrom bolevom razdrazhenii pod zashchitoi élektroigloanalgezii.

The concentrations of endogenous opiates (beta-endorphin, methionine-enkephalin, leucine-enkephalin) in the spinal fluid and arterial blood plasma has been studied in 16 dogs, using the model of acute pain stimulation under electroacupuncture analgesia (EAA). It has been shown that pain stimulation under EAA is accompanied by a significant increase in methionine-enkephalin++ and leucine-enkephalin concentrations (by 244 and 69.4%, respectively) in the spinal fluid. beta-endorphin level tends to increase. There is also a trend towards the reduction in beta-endorphin and methionine-enkephalin concentrations in the arterial blood plasma, which is indicative of effective antinociceptive stimulation of the endogenous opiate system. However, by the end of the first hour a decrease of methionine-enkephalin and leucine-enkephalin levels in the spinal fluid was paralleled by a trend towards beta-endorphin and methionine-enkephalin increase and a significant leucine-enkephalin increase in arterial blood plasma, which can account for the exhaustion of the opiate system.