title: [Morphologic reactions and long-term vasal tonus behavior of the coronary microvascular system in different states of spontaneous hypertension in the rat].
abstract: The morphological reactions and the long-term vasotonus behaviour of the coronary microvasculature including its smallest ramifications as well as the relationships existing between these reactions and the myocardial activity in the different stages of spontaneous hypertension of rats (SHR) are unknown. Therefore 80 1-12 month-old male SH- and 60 normotensive Wistar control rats were histomorphometrically investigated. Already in the prestage of hypertension (1 month) an increase of wall thickness and phosphatase activity in blood vessels alpha less than 10,5 microns occurred. These appearances of vasotonus increase were regressed in the acute phase (2nd-4th month). When the rise of myocardial activity is lowered in the stabile stage the mentioned signs of vasotonus increase returned (6th month) and showed a strong spreading in the late stage (12th month), which is characterized by enzyme histochemically detected disturbances of heart muscle metabolism. The behaviour of long-term vasotonus of the microvasculature and myocardial metabolism in 6 month-old and older rats provides a hypothesis concerning the cause of the unknown increase of coronary contraction in the stabile phase. It points to the existence of a vicious circle which perhaps plays a role in the genesis of heart insufficiency in hypertension.
mesh_terms: D000818:Animals; D003326:Coronary Circulation; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D007223:Infant; D007231:Infant, Newborn; D008833:Microcirculation; D009200:Myocardial Contraction; D009206:Myocardium / Q000201:enzymology; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D010744:Phosphoric Monoester Hydrolases
vernacular_title: Morphologische Reaktionen und Langzeitvasotonusverhalten des mikrovaskulären Koronarsystems in verschiedenen Stadien der spontanen Hypertonie der Ratte.