Methamphetamine HCl Research Articles

Life span and pathology in offspring following nicotine and methamphetamine exposure.

Seventy-nine primiparous Sprague-Dawley rats received s.c. injections of either 3.0 mg/Kg of pure nicotine, 5.0 mg/Kg of methamphetamine HCL, 5.0 MG/Kg of saline vehicle, or received no injections during the 21 day gestational and 19 day nursing period. Male offspring were divided into 3 groups at weaning. The autopsy animals (n = 80) were sacrificed at selected periods during the life span, the aging animals (n = 60) were weighed monthly until death, and the behavioral rats (n = 48) were monitored on a variety of behavioral tasks throughout their life span. Measures reported here include life span data, organ pathology and tumor formation. Significant differences among the four offspring groups were found for tumor incidence, gross pathology, and age at death in the autopsy group; and weight maintenance in the aging group.

Growth, development and activity in rat offspring following maternal drug exposure.

Seventy-nine Sprague-Dawley derived primimparous rats were injected subcutaneously throughout pregnancy and the nursing period with either (1) 30 mg/kg of pure nicotine, (2) 5.0 mg/kg methamphetamine HCL, (3) saline vehicle, or, (4) non-injected. Vital and developmental measures were taken on the offspring throughout the nursing period and for one additional week. Metamphetamine-injected females had a shorter, and nicotine-injected females a longer gestational period, and both gained less weight over the 21-day period than the control groups. The pups of methamphetamine and nicotine dams were significantly underweight at birth and the 28 day postnatal period and exhibited developmental delay. Male offspring were divided into behavioral, aging, and autopsy on Day 28. Male offspring of methamphetamine-injected dams remained significantly lighter in weight for the first 15 months of life (aging groups). Their counterparts in the behavioral groups and the offspring of non-injected dams exhibited significantly greater activity for eight of the first twelve monthly assessments which began at 90 days of age. Additional vital, performance, and sensory measures will continue throughout the lifespan of the animals.

Dose-dependent facilitation or supression of rat fighting by methamphetamine, phenobarbital, or imipramine.

To clarify the effects of different doses of methamphetamine HCl, Na phenobarbital, and imipramine HCl on aggressive behavior, the drugs were administered to pairs of rats trained to regularly fight on an electric shock grid. Fighting time and motor activity were measured during the shock sessions. Each drug was given to a different group of rats, in the following doses (mg/kg i.p.): methamphetamine HCl 0, 0.25, 0.50, 1, 2, and 4; Na phenobarbital 0, 5, 10, 20, 40, and 80; imipramine HCl 0, 2.5, 5, 10, and 20. At lower doses methamphetamine and phenobarbital both stimulated fighting behavior, and at higher doses both reduced it. Motor activity rose above control with lower doses of both of these drugs; it fell markedly with higher doses of phenobarbital, while remaining elevated at higher doses of methamphetamine. Imipramine reduced fighting time at higher doses. The results show that, depending upon the dose, the “stimulant”, methamphetamine, and the “sedative”, phenobarbital, can both increase or decrease aggressive behaviors. Together with previous animal studies, these findings fit with clinical observations that amphetamines and barbiturates can increase aggressive behavior, and suggest that dose may be important in that increase.

Improved Colorimetric Method for Assay of Amphetamines in Urine

Abstract The increasing abuse of drugs makes it imperative to have rapid, selective methods for their detection. Methods for amphetamines in which methyl orange is used as a reagent are subject to interference by a number of drugs. In the present modified, improved method, amphetamines combine with methyl orange to form a chromogen that follows Beer’s law at 515 nm to amphetamine concentrations of 10 mg/100 ml. Most interfering drugs are removed by pre-extraction into chloroform at pH 5.5. Of over 40 commonly used drugs, including organic bases and alkaloids, only amphetamine, dextroamphetamine, methamphetamine, and pentazocine HCl ("Talwin") react to produce a chromogen in this method. Recovery of amphetamine added to serum and urine is essentially 100%, as compared with aqueous standards taken through the entire procedure. The coefficient of variation is 8.9%. The method described, far more (but not completely) selective for amphetamines than previous methyl orange methods, is rapid, precise, and sensitive, which makes the method valuable in drug abuse screening programs—for which the speed is even greater, because only information on the qualitative presence or absence of amphetamines is required.

Electron microscopic studies concerning the structural mechanism of the development of mental disturbance in experimental chronic methamphetamine poisoning.

In 8 male albino strain guinea pigs, 1 mg/kg of methamphetamine HCl was injected daily for 7 months to 1 year to produce chronic methamphetamine intoxication and to study the fine structure of the brain electron microscopically. The following results were obtained: In view of these findings, as well as the clinical neurological symptoms in patients with methamphetamine poisoning, the coalescence of membranes between nerve processes and the appearance of membranous structures in all portions of nerve cell cytoplasm from body to nerve endings appear to represent the most important findings, they probably produce a profound disturbance in the system of nerve conduction and transmission.