[Effect of active immunization with dopamine- and norepinephrine-protein conjugated on neurochemical and neurophysiologic parameters of withdrawal syndrome in chronically morphine-treated rats]

The impact of induction of antibodies to the catecholamines (CA) dopamine (DA) and norepinephrine (NE) during active immunization of rats with CA conjugated to protein (BSA) on morphine dependence, withdrawal syndrome, and neurotransmitter status was studied during 14-day morphine treatment. DA-BSA and NE-BSA immunization of rats provided lower plasma DA concentrations in naloxone-precipitated opiate withdrawal. However, it failed to lead to normalization of hypothalamic DA levels and exacerbated the withdrawal syndrome. In immunized rats, including those immunized with BSA, the hypothalamic levels of DA and epinephrine (E) were even higher than in morphine-treated rats previously unimmunized. The aggravation of withdrawal symptoms was especially pronounced in rats preimmunized with NE-BSA, which could be due to a significant NE rise in the brain tissue.

[Induction of autoantibodies to serotonin and catecholamines in chronically morphine addicted rats with manifestations of abstinence syndrome]

The possibility of formation of autoantibodies to neurotransmitters has been studied in experimental model of opiate addiction. Chronic treatment of rats with morphine that leads to formation of dependence, causes induction of antibodies to norepinephrine, dopamine and serotonin. The latter could be considered as indicators of impaired neurotransmitter metabolism. Induction of autoantibodies to neurotransmitters could be a sort of defence mechanism in opiate addiction.

Induction of antibodies to morphine during chronic morphine treatment in rodents and opiate addicts

The phenomenon of induction of antibodies to morphine in morphine-treated animals and opiate addicts was shown by means of ELISA. The reaction of the immune system to injections of a morphine solution had the characteristics of a primary immune response. Opiate addicts differed from normal controls in the level of antibodies to morphine of IgM class. Elevated levels of such antibodies could be detected in about 70-80% of addicts with regular longterm opiate use when the time since the last drug intake did not exceed 60 days. Antibodies to morphine could serve as indicators of chronic opiate use especially in periods long after the last drug intake.

[Antibody formation to morphine and neuromediators in morphinized rats]

The paper demonstrates induction of antibodies to morphine and neurotransmitters (dopamine, norepinephrine, serotonin) in rats treated with intraperitoneal injections of morphine hydrochloride during 2 and 4 weeks in increasing doses. A contribution of such antibodies to the mechanisms of morphine tolerance and formation of physical dependence is considered.

Biochemical resistance to development of morphine-dependence in rats: biogenic amines, its receptors and antibodies

The level of norepinephrine (NE), epinephrine (E) and dopamine (DA) in hypothalamus and blood plasma along with antibodies to NE, DA and serotonin (5-HT) and characteristics of alpha 1-, alpha 2-adrenergic, D2-dopaminergic and S2-serotoninergic receptors in synaptic brain membranes were studied in two groups of rats predisposed or resistant to the formation of physical morphine dependence. The resistant animals were characterized by a significant elevation of DA levels in blood plasma, elevation of antibodies to NE, and by higher concentration of alpha 2-adrenergic receptors in the brain cortex and of D2-receptors in striatum. The affinity of D2-receptors to dopamine in resistant rats also was higher than in predisposed animals. The other parameters studied did not differ significantly between the two groups. These findings suggest that the increased activity of DA and NE neurotransmitter systems can be a cause for the genetic resistance of some individuals among Wistar rats to the formation of physical dependence on morphine.

[Effects of morphine on adenylate cyclase activity in lymphocytes of healthy subjects and patients with alcoholism and opiate addiction]

The morphine dose 10(-7) M had practically no effect on adenylate cyclase (AC) activity in lymphocytes of healthy controls (n = 20). The same dose of morphine had a pronounced stimulating effect on the AC activity in lymphocytes of alcoholics in withdrawal (n = 16). In the group of opiate addicts in withdrawal (n = 9) morphine had also a stimulating effect, which differed significantly from controls (33.7 +/- 13.8; P. 0.02). The range of fluctuation of morphine influence on AC activity during the first week of hospitalization was 162.9 +/- 33.0% in alcoholics and 30.4 +/- 4.6% in opiate addicts (P 0.01).

Morphine influence on adenylate cyclase activity in peripheral blood lymphocytes of alcoholic patients

The effect of morphine on adenylate cyclase activity in lymphocytes was tested in 20 normal controls, 16 alcoholics in withdrawal and 9 sober alcoholics. Alcoholics in withdrawal were characterized by a significantly increased stimulatory effect of morphine, whereas sober alcoholics showed an inhibitory effect. The morphine effect was abolished by naloxone and correlated with the severity of withdrawal and alcohol intoxication.