Lithium inhibits human sperm motility in vitro.

Lithium is a widely prescribed drug used for the treatment of bipolar affective illness. Previous reports on its effects on sperm motility and male fertility are conflicting. The effect of lithium on human sperm motility was examined in vitro using the modified transmembrane migration method. This technique takes account of the dilution of lithium that occurs during the incubation. Lithium inhibits human sperm motility in vitro in concentrations comparable with those reported to be achieved in semen after oral administration.     

Myopathies of the lower extremities

The myopathies that can manifest themselves within the lower extremity are reported here and can serve as a guideline for clinicians in the early diagnosis of these disabling conditions. The classification of these disease entities based on signs and symptoms is significant if correlated with the age of the patient at the time of onset, the evolution and course, and the type of familial inheritance. This article can also aid the practitioner in assessing and planning the course of treatment for a particular patient.     

Characterization of unique ADTN-catecholamine binding sites in the iris root-ciliary body of rabbits

A binding site for tritiated 2-amino-6, 7-dihydroxy-1, 2,3,4-tetrahydronaphthalene (ADTN) has been partially characterized in the rabbit iris root-ciliary body. Binding of ADTN is proportional to protein content and requires at least 60 minutes to reach equilibrium. Binding is saturable, with a Kd of 27 +/- 1 nM and a Bmax of 2.1 +/- .3 pmol/mg protein (mean +/- SEM). Dopamine competes for this site with a Ki of 100 nM and apomorphine with a Ki of 180 nM. This site is not blocked by L-timolol, phenoxybenzamine, or by several DA1 and DA2 antagonists. It appears to be a new type of catecholamine binding site, of a type not observed outside the anterior eye. It is possible that some of the effects of dopamine on intraocular pressure are mediated through this binding site.     

Study of talc for pharmaceutical use. Trials of pharmacopoeias

A study has been carried out on the possible pharmaceutical use of spanish talcs following the normalized assays of the main european pharmacopoeia and other quantitative methods. Only the talc nr3, not processed, meets all the assays of pharmacopoeia. The samples 2 and 4 (crushed) exceed the highest tolerated content in chlorides. The talc 1 (also crushed) only meets the loss on drying. The measures of some of these assays by using quantitative methods lead to more correct results and even sometimes in opposition with those obtained by pharmacopoeia methods. The particle size estimated by shifting and sedimentation shows that the crushed talcs are silty, whereas the only talc not processed is sandy. Considering the medium sizes estimated by scanning microscopy, it can be said that the pulverization of the talcs 1, 2 and 4 is characteristic of a micronization.     

Additional myocardial salvage by coadministration of the epoprostenol analog taprostene to recombinant single-chain urokinase-type plasminogen activator in a canine coronary thrombosis model

In open chest dogs myocardial ischemia was induced by formation of an occlusive thrombus in the left anterior circumflex artery (LCX). Reperfusion of the LCX was achieved by infusion of the fibrin specific recombinant single-chain urokinase-type plasminogen activator (r-scu-PA). The myocardial salvage by r-scu-PA alone and in combination with the epoprostenol (prostacyclin) analog taprostene (CG 4203) was compared. There were four experimental groups: group 1 (n = 4) did not receive any treatment after LCX thrombosis; in group 2 (n = 9) at 100 min after LCX thrombosis r-scu-PA (20 micrograms.kg-1.min-1 i.v. for 30 min) was infused; in groups 3 and 4 treatment with taprostene started concomitantly with r-scu-PA infusion. The taprostene infusions lasted for 120 min and the doses were 0.1 microgram.kg-1.min-1 in group 3 (n = 6) and 0.215 microgram.kg-1.min-1 in group 4 (n = 6). Time to r-scu-PA-induced recanalisation ranged from 18-22 min with no significant difference between groups 2-4. Percent of left ventricle at risk did not differ between the groups. Infarct size as percent of the risk zone was 48.3 +/- 7.7 in group 1, 25.3 +/- 3.7 in group 2, 21.3 +/- 6.5 in group 3 and 17.1 +/- 3.5 in group 4 (p less than 0.05 groups 2-4 vs group 1). Incidence of ectopic beats increased after r-scu-PA-induced reperfusion in groups 2-4, but was significantly reduced by taprostene.(ABSTRACT TRUNCATED AT 250 WORDS)     

Lack of tolerance to nicotine-induced dopamine release in the nucleus accumbens

The extent to which repeated administration produces tolerance to nicotine-induced increases in dopamine transmission in the nucleus accumbens was investigated in rats. In vivo microdialysis was used to sample extracellular dopamine and metabolites after a nicotine challenge (0.35 mg/kg) in (1) naive rats, (2) acutely pretreated rats (1 prior nicotine injection), and (3) chronically pretreated rats (12-15 prior daily nicotine injections, 0.35 mg/kg per injection). Nicotine increased extracellular DA and its metabolites, and these increases were not significantly altered by either acute or chronic prior exposure to the drug. The failure to find evidence of tolerance is compatible with the hypothesis that the mesolimbic dopaminergic system is a substrate for the reinforcing properties of chronically administered nicotine.