Effects of Inhibitors of Collagen Maturation on Hypertension in Rats

Abstract

The effects of β-aminopropionitrile (BAPN), an inhibitor of collagen maturation, have been examined in three models of hypertension in rats. It is shown for the first time that BAPN has a rapidly developing antihypertensive action in rats with renal (one kidney-one clip) hypertension. The compound also lowered blood pressure in spontaneously hypertensive rats. In both these experiments although BAPN lowered blood pressure it did not affect the hypertension-induced hypertrophy of the aorta. BAPN suppressed the rise in blood pressure during the developing phase of deoxycorticosterone acetate-salt-induced hypertension and in this model the compound also prevented the accompanying aortic hypertrophy. However, another inhibitor of collagen synthesis and maturation, 3,4-dehydroproline, completely suppressed aortic hypertrophy but failed to prevent the rise in blood pressure in deoxycorticosterone acetate-salt hypertension. It is concluded that: (1) BAPN may have a direct antihypertensive action, and (2) inhibition of aortic hypertrophy alone cannot prevent the rise in blood pressure in the developing phase of deoxycorticosterone acetate-salt hypertension.

Effects of Chronic Beta-Aminoproprionitrile Treatment on Rat Carotid Artery

“…In addition, pretreating animals prior to the development of experimental hyper tension inhibited or prevented the increase in arterial pressure that would have occurred along with changes in collagen synthesis and content. These results o f Iwatsuki et al [3] seem to support the hypothesis of Folkow et al [2], On the other hand, Franklin et al [5] demonstrated that the anti-hypertensive ef fects o f BAPN and its actions on collagen synthesis and content were dissociated in the aorta of several different models of hyper tension. Franklin et al [5] observed that when they administered BAPN to sponta neously hypertensive and renal hypertensive rats, blood pressure fell in both animal m od els without a reduction in the aortic hyper trophy that had been associated with hyper tension.…”

“…These results o f Iwatsuki et al [3] seem to support the hypothesis of Folkow et al [2], On the other hand, Franklin et al [5] demonstrated that the anti-hypertensive ef fects o f BAPN and its actions on collagen synthesis and content were dissociated in the aorta of several different models of hyper tension. Franklin et al [5] observed that when they administered BAPN to sponta neously hypertensive and renal hypertensive rats, blood pressure fell in both animal m od els without a reduction in the aortic hyper trophy that had been associated with hyper tension. These authors suggested that an ad ditional direct antihypertensive effect of BAPN was responsible for decreasing blood pressure unrelated to its effects on collagen synthesis and accumulation in blood ves sels.…”

“…In view of the suggestion of Franklin et al [5], it was the objective of the experiments described herein to evaluate the effects of chronic BAPN treatm ent on the active and passive mechanics of arteries in the young rat.…”