[Effect of ethanol, diazepam, and reserpine on the activity of angiotensin-converting enzyme and carboxypeptidase in normal state and during stress]. / Vliianie étanola, diazepama i rezerpina na aktivnost' angiotenzinprevrashchaiushchego fermenta i karboksipeptidazy v norme i pri stress.

There was discovered a resemblance in the influence of some pharmacological agents such as ethanol, diazepam and rezerpine on the activity of enzymes of metabolism of biological active peptides in the blood under emotional stress. It was determined that the character of the influence depends on the emotional status of animals. The possibility of drawing both angiotensin converting enzyme and carboxypeptidase N in the stress-protection action of the ethanol, diazepam and rezerpine is discussed.

[Effect of captopril on angiotensin-converting enzyme activity and animal behavior in the "open field" test]. / Vliianie kaptoprila na aktivnost' angiotenzinprevrashchaiushchego fermenta i na povedenie krys v teste "otkrytogo polia".

Captopril was investigated for its effects on the activity of angiotensin-converting enzyme in the rat blood serum, pituitary, hypothalamus, and striatum, as well as for those on the animals, behavior in the open-field test. During its single administration the agent was found to lower the activity of angiotensin-converting enzyme in all the examined brain regions and serum. During chronic administration captopril decreased the mobility of the animals in the open-field test, diminished, the activity of the enzyme in the hypothalamus and striatum and enhanced it in the pituitary and serum. It is suggested that the effect of captopril might be due to imbalance in the changes of angiotensin-converting enzyme activity in various brain regions of the rats.

[Partial characteristics of the basic phenylmethylsulfonylfluoride-inhibited carboxypeptidase from cat brain]. / Chastichnaia kharakteristika osnovnoi fenilmetilsul'fonilftorid- ingibiruemoi karboksipeptidazy iz golovnogo mozga koshki.

Cat brain carboxypeptidase releasing C-terminal arginine from the synthetic substrate, dansyl-Phe-Leu-Arg, was partially characterized. The enzyme has a molecular weight of 100-120 kDa, displays the maximal activity at pH 6.0-6.5 and is strongly inhibited by phenylmethanesulfonylfluoride and 4-chloromercuribenzoate, less strongly (by 40%) by iodoacetamide and is not inhibited by N-ethylmaleimide, 2-mercaptoethanol, EDTA, Co2+ and guanidinoethylmercaptosuccinic acid. The Km values for the hydrolysis of dansyl-Phe-Leu-Arg and dansyl-Phe-Ala-Arg by soluble carboxypeptidase are 48 and 96 microM, respectively. By all properties, this carboxypeptidase differs from other known carboxypeptidases. Possible participation of the enzyme in neuropeptide metabolism is discussed.

[Effect of glucocorticoids on activity of soluble and membrane-bound forms of carboxypeptidase H in vivo]. / Vliianie gliukokortikoidov na aktivnost' rastvorimoi i membranosviazannoi form karboksipeptidazy H in vivo.

Inhibition of soluble and membrane-bound carboxypeptidase H in rat hypothalamus, striatum and pituitary gland by hydrocortisone and dexamethasone treatment in vivo has been established. Differences in the dynamics of change in the activity were determined by the action of hydrocortisone and dexamethasone. Differences of the dynamics of change in soluble and membrane-bound carboxypeptidase H activity were also observed. Possible causes of these differences are discussed.

[Effect of captopril and reserpine on the activity of certain neuropeptide metabolism enzymes]. / Vliiane kaptoprila i rezerpina na aktivnost' nekotorykh fermentov obmena neiropeptidov.

Chronic consumption of the highly specific angiotension-converting enzyme inhibitor captopril was found to decrease the activity of the enzyme in the rat hypothalamus and striatum and to enhance it in the pituitary and blood serum. The agent also increased the activity of carboxypeptidase N in the serum and that of carboxypeptidase H in the pituitary. Reserpine, a catecholaminergic blocking agent, reduces the pituitary and serum activities of angiotensin-converting enzyme and activates soluble carboxypeptidase H in the pituitary and striatum and membrane-bound carboxypeptidase in the hypothalamus and striatum. Possible mechanisms of action of captopril and reserpine on the activity of the enzymes in question, as well as a contribution of these enzymes to their antihypertensive effect are discussed in the paper.

[The effect of emotional stress on carboxypeptidase H activity in sections of the rat brain with varying sensitivity to it]. / Vliianie émotsional'nogo stressa na aktivnost' karboksipeptidazy H v otdelakh golovnogo mozga krys s razlichnoi ustoichivost'iu k nemu.

The activity of carboxypeptidase H involved in metabolism of neuropeptides was studied in rats resistant and predisposed to emotional stress under normal and stress conditions. The enzymatic activity was higher in the striatum and hypothalamus of the rats predisposed to stress than that of stress-resistant animals. Emotional stress resulted in activation of the enzyme in these both groups of animals, while the dynamics of the enzyme activity depended on the resistance of animals to stress and the poststress interval. There was a correlation between the activity of carboxypeptidase H and the content of neuropeptides in animals with varying stress-resistance.

[The interconnection between the activity of carboxypeptidase N and angiotensin-converting enzyme]. / O vzaimosviazi mezhdu aktivnost'iu karboksipeptidazy N i angiotenzin- prevrashchaiushchego fermenta.

Inhibition of the angiotensin-converting enzyme by guanidino-ethylmercaptosuccinic acid, a highly specific inhibitor of carboxypeptidase H, and inhibition of carboxypeptidase H by captopril, a highly specific inhibitor of the angiotensin-converting enzyme, in vivo were studied. Guanidinoethylmercaptosuccinic acid and captopril had no effect either on the angiotensin-converting enzyme or the carboxypeptidase H activities in vitro. The putative mechanisms of the inhibitors effects of the enzyme activity are discussed.

[Activity of soluble and membrane-bound forms of carboxypeptidase H in regions of the rat brain in emotional stress]. / Aktivnost' rastvorimoi i membranosviazannoi form karboksipeptidazy H v otdelakh golovnogo mozga krys pri émotsionalnom stresse.

Carboxypeptidase H activity in the brain of rats with different resistance to emotional stress was shown to change differently. The enzyme activity during stress in hypophysis was higher in predisposed rats but in striatum and hypothalamus it was lower in the animals stable to the stress. The activity of soluble and membrane bound enzyme in hypophysis during the emotional stress was changed in different direction but in striatum and hypothalamus the activity of both forms of the enzyme was changed equally. The activity of a soluble form was changed larger than in membrane-bound one. Differences of functions of soluble and membrane-bound forms and their participation in emotional stress development in rats with different tolerance to stress are discussed.

[The effect of diazepam on the activity of carboxypeptidase N and the angiotensin-converting enzyme in sections of the brain of rats with differing normal emotionality and in emotional stress]. / Vliianie diazepama na aktivnost' karboksipeptidazy N i angiotenzinprevrashchaiushchego fermenta v otdelakh mozga krys s razlichnoi émotsional'nost'iu v norme i pri émotsional'nom stresse.

Diazepam increased the carboxypeptidase H activity and decreased the angiotensin converting enzyme activity in the rat brain. Joint action of diazepam and emotional stress changed the carboxypeptidase H activity to the least extent and the angiotensin converting enzyme activity to the utmost extent as compared to the agents' separate effects. The role of both enzymes in the diazepam effect is discussed.

[Angiotensin-converting enzyme activity in regions of the rat brain possessing varying resistance to emotional stress, in health and in stress]. / Aktivnost' angiotenzin-prevrashchaiushchego fermenta v otdelakh golovnogo mozga krys, obladaiushchikh razlichnoi ustoichivost'iu k émotsional'nomu stressu, v norme i pri stresse.

Angiotensin converting enzyme activity in hypophysis and S. grisea of the stable rats was higher but in hypothalamus it was lower than in the predisposed ones. Activity of the enzyme depended on the area, degree of tolerance to stress and a kind of stress. The role of angiotensin converting enzyme at the determination of tolerance to emotional stress and stress development was discussed.

[Carboxypeptidase N and angiotensin-converting enzyme activities in the blood serum of rats with different resistances to emotional stress]. / Aktivnost' karboksipeptidazy N i angiotenzinprevrashchaiushchego fermenta v syvorotke krovi krys s razlichnoi ustoichivost'iu k émotsional'nomu stressu.

The carboxypeptidase N and angiotensin converting enzyme contents was 1.4-1.5-fold higher in emotionally stable rats as compared with those predisposed to an emotional stress. Possible causes of this phenomenon are discussed.

[Carboxypeptidase N and angiotensin converting enzyme activity in rat blood serum in health and during emotional stress]. / Aktivnost' karboksipeptidazy N i angiotenzinprevrashchaiushchego fermenta v syvorotke krovi krys v norme i pri émotsional'nom stresse.

The effect of emotional stress on both carboxypeptidase N and angiotensin converting enzyme activities in the blood serum of stable and predisposed rat was studied. It was found that activities of both enzymes in serum of stable rat was higher as compared with those predisposed to emotional stress. During emotional stress a decrease of both enzymes activities was observed. Both enzymes activities in rats with different degrees of tolerance to emotional stress were changed differently.

[Purification and physico-chemical properties of soluble carboxypeptidase N from cat brain gray matter]. / Ochistka i fiziko-khimicheskie svoistva rastvorimoi karboksipeptidazyN iz serogo veshchestva golovnogo mozga koshki.

Using affinity chromatography on diasorb-L-arginine and polyacrylamide gel electrophoresis, soluble carboxypeptidase H (E. C. 3.4.17.10) has been isolated from cat brain cortex and purified 598-fold with a 16% yield. The enzyme has a molecular mass of 50 kDa, consists of one polypeptide chain, and displays the maximum activity at pH 5.6. Carboxypeptidase H is a thiol-dependent metalloenzyme and contains a Zn2+ ion in its active center. The Km and V values for dansyl-Phe-Leu-Arg are 100 +/- 5 microM and 12.5 +/- 1.4 microM/min/mg of protein, respectively. The existence of two forms of soluble carboxypeptidase differing in isoelectric points and pH optima has been demonstrated. The enzyme with a pI of 4.8 has a pH optimum at 5.5-5.6, while that with a pI of 5.25-at 6.0.