A histochemical study of cerebral cortical vessels and ganglionic vessels of the caudatoputamen in aging normotensive rats.

Abstract

SUMMARYThe goal was to describe the metabolic profile of ganglionic and cortical arteries and arterioles in aging normotensive male rats. Five enzymes indicative of key metabolic pathways in the vessel walls were semiquantitatively evaluated using bright-field histochemical microscopy. Lactate dehydrogenase showed significant reactivity which increased with vessel diameter in cortical and ganglionic vessels in all age groups tested. Succinate dehydrogenase and cytochrome oxidase showed little reactivity in both cortical and ganglionic vessels, suggesting a reduced role for aerobic metabolic pathways. Myosin ATPase reactivity was high in cortical and ganglionic vessels. Only this enzyme showed an increased reactivity that was correlated with the age and diameter of the vessel. Glucose-6-phosphate dehydrogenase reactivity was more pronounced in cortical than ganglionic vessels, suggesting that the hexose-monophosphate-shunt may be more active in the cortical vessels. There were no regional differences in enzyme reactivity throughout the caudatoputamen. In conclusion, both the cortical and ganglionic vessels are metabollcally active, with significant anaerobic gh/colysis, and reduced, but observable capacity for aerobic metabolism. The decreased myosin ATPase reactivity and the low level of glucose-6-phosphate dehydrogenase reactivity in the ganglionic arterioles of senescent rats may contribute to the susceptibility of these vessels to cerebrovascular accidents. Stroke Vo! 16, No 2. 1985 THE ARTERIAL SUPPLY to the cerebrum and subcortical structures in the rat and man have many similarities, particularly in the pathophysiology of stroke. Terminal branches of the internal carotid arteries, branches from the anastomotic circle, and the posterior cerebral arteries supply the cerebral cortex in rat and man.2 3 All of these vessels provide a dense network of ganglionic arterioles that nourish the basal ganglia, including the caudatoputamen (CPU) and globus pallidus.3 Although the vascular bed of the cerebrum and subcortical structures have been described, little is yet known regarding the metabolism of these vessels.4 " 8 Furthermore, even though age-related structural changes are reported for both cortical and ganglionic vessels in man and other experimental animals, 9 "' 5 virtually nothing is known regarding the effects of aging on cerebral vascular metabolism.The present study utilizes histochemical methodology to semiquantitatively evaluate enzymes of key metabolic pathways in the muscular walls of vessels supplying the neocortex (cortical vessels) and ganglionic vessels in the CPU of aging normotensive male rats. The five enzymes evaluated are indicators of anaerobic glycolysis, the Krebs cycle and respiratory chain (aerobic metabolism), the hexose-monophosphate-shunt, and the availability of myosin ATPase. Our goal was to delineate the metabolic profile of aging stroke-prone ganglionic vessels and of cortical vessels, from which the former arise. Methods Twenty-three male rats (Charles River, COBS CD outbred ...

Mesencephalic Arteriolar and Neuronal Metabolic Profiles from Fresh and in vitro Incubated Tissue Sections in the Mouse: A Histochemical Approach

“…the larger arterioles demon strate moderate to strong reactivity for this enzyme. Like the midbrain arterioles presently described in the mouse, Rieke and Cannon [ 1985] and Cannon et al [ 1985] demon strated that arterioles of the rat caudate nucleus were also capable of utilizing aerobic and anaerobic pathways.…”

“…some his tochemical studies on arteriolar reactivity in the central nervous system have been reported [Cannon and Gelderd. 1983: Rieke and Cannon. 1985: Can non et al.…”

Thalamic arterial pattern: An endocast and scanning electron microscopic study in normotensive male rats

“…Smooth muscle in small arterioles is the key element for maintenance of vascular tone and the lumenal diameter (Milnor, 1974) and therefore for the regulation of blood flow through the arteriole (Edvinsson et al, 1979). Rieke and Cannon (1985) have shown that as ganglionic arteries (penetrating muscular arterioles) age there is a significant decrease in the availability of myosin ATPase in the muscular wall. The loss of ATPase may lead to a reduction in muscle tone and an increase in vessel diameter.…”

“…The use of the lowviscosity methyl methacrylate monomer perfused through the left heart or the aortic arch produces an accurate replica of the arterial vascular supply and the capillary bed of diverse vascular trees (Rieke et al, 1981;Hossler and Olson, 1984). The pattern of the arterial supply to the thalamus in the rat has not been defined, yet such a definition would seem essential for use of the rat as a model to study structural and metabolic changes related to aging and the mechanisms underlying stroke in humans (Rieke and Cannon, 1985). The relevance of defining the rat model for the thalamic arterial supply lies in the fact that the thalamus is a frequent site of hemorrhagic strokes in man (approximately 10-15%, Kase and Mohr, 1986).…”

Cocaine: Long-Term Administration Depletes Cardiac Enzymes in the Rat

“…External vessel diameters were determined directly from photographic prints and by utilization of an eye-piece micrometer. Vessels with diameters less than 80 pm were considered microvessels (arterioles) [ 14,15]. Using the Leitz photometer DADS, described below, for each histochemical reaction, approximately 200 arterioles from each animal were examined and were photographed at the same light inten sity.…”