The common epithet of “fight or flight” is being enlarged to be “fight, flight, or fright” or even “fight, flight, fright, or freeze.” Cannon’s original contribution was a catchy phrase to express some of what the nervous system does in response to a threat, but it is incomplete. The sympathetic system is responsible for the physiological responses to emotional states. The name “sympathetic” can be said to mean that (sym- = “together”; -pathos = “pain,” “suffering,” or “emotion”).
http://cnx.org/content/m46582/latest/?collection=col11496/latest
Tuesday, February 18, 2014
Thursday, February 6, 2014
prolongation of the isometric (tension) period (TP) of the left ventricle occurred in the majority (72 per cent) of all cases after sympathectomy
The prolongation of the isometric (tension) period (TP) of the left ventricle which occurred in the majority (72 per cent) of all cases after unilateral or bilateral transthoracic sympathectomy (without or with unilateral or bilateral transthoracic splanchnicotomy) indicates a diminution of inotropic cardiac action. It can be assumed to correspond to the cholinergic (vagal) preponderance which results from a partial or complete sympathetic denervation of the heart. Reduction of the pulse pressure oc-
curred in 56 per cent of the cases, probably due to the same mechanism.
www.chestjournal.org/content/38/4/423.full.pdfby W RAAB - 1960
www.chestjournal.org/content/38/4/423.full.pdfby W RAAB - 1960
Sunday, February 2, 2014
histochemical comparison of the normal and chronically sympathectomized heart
Jones CE, Cannon MS.
Using histochemical techniques, the reactivities of selected enzymes and other metabolic components were examined in the myocardium, coronary arteries, and coronary arterioles of normal, two-week-sympathectomized, and sham-operated canine hearts. There were no differences in the histochemistry of coronary arteries in any of the hearts, but important differences were noted in the myocardium and especially in the arterioles. The reactivities of the enzyme glucose-6-phosphate dehydrogenase and the nucleic acids were increased in arterioles of the sympathectomized heart, possibly indicating an increased protein synthesis. The reactivities of succinate dehydrogenase, NAD-isocitrate dehydrogenase, and cytochrome oxidase were reduced in myocardium and arterioles of sympathectomized hearts as well as in arterioles of sham-operated hearts; the changes were greater in the sympathectomized arterioles where there was also observed an increase in reactivity of lactate dehydrogenase. These findings suggest a depression in aerobic metabolic capacity and, in the case of the sympathectomized arteriole, imply a possible shift in adaptation from aerobic to anaerobic metabolism.
Histochem J. 1980 Jan;12(1):9-22.
Using histochemical techniques, the reactivities of selected enzymes and other metabolic components were examined in the myocardium, coronary arteries, and coronary arterioles of normal, two-week-sympathectomized, and sham-operated canine hearts. There were no differences in the histochemistry of coronary arteries in any of the hearts, but important differences were noted in the myocardium and especially in the arterioles. The reactivities of the enzyme glucose-6-phosphate dehydrogenase and the nucleic acids were increased in arterioles of the sympathectomized heart, possibly indicating an increased protein synthesis. The reactivities of succinate dehydrogenase, NAD-isocitrate dehydrogenase, and cytochrome oxidase were reduced in myocardium and arterioles of sympathectomized hearts as well as in arterioles of sham-operated hearts; the changes were greater in the sympathectomized arterioles where there was also observed an increase in reactivity of lactate dehydrogenase. These findings suggest a depression in aerobic metabolic capacity and, in the case of the sympathectomized arteriole, imply a possible shift in adaptation from aerobic to anaerobic metabolism.
Histochem J. 1980 Jan;12(1):9-22.
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