Cannabinoids negatively modulate striatal glutamate and dopamine release and behavioural output of acute D-amphetamine.

The cannabinoid system plays a regulatory role in neurotransmission and is involved in the central actions of psychostimulants. This complex interaction between the cannabinoid system and psychostimulants represents a potential pharmacological target for psychosis and addiction. However, most studies have focused on cocaine, therefore, it is unclear whether these findings can be extended to other psychostimulants such as the amphetamines. The present study investigated the effects of WIN55,212-2, a synthetic cannabinoid and SR141716A, a CB1 receptor antagonist, on D-amphetamine-induced locomotor activity and extracellular dopamine and glutamate release in the striatum. Rats were either observed for locomotor activity or glutamate and dopamine neurotransmitter release in the striatum using in vivo microdialysis following intraperitoneal co-administration of D-amphetamine with WIN55,212-2 or SR141716A. Our results demonstrated that d-amphetamine per se induced hyperlocomotion and enhanced dopamine and glutamate release, as expected. WIN55,212-2 dampened these effects when co-administered with d-amphetamine, while alone it displayed its characteristic biphasic motor profile coupled with increases in dopamine and decreases in glutamate release. SR141716A at high doses reduced D-amphetamine-induced hyperlocomotion and completely reversed enhanced dopamine and glutamate release but alone had no effect. These findings validate the capacity of the cannabinoid system to modulate amphetamine-induced behaviour and its neurochemical output, in a state-dependent manner, providing insight into aspects of the neurobiological substrate that underlies amphetamines' psychotogenic and addictive properties.

Foliar and cortex oleoresin variability of silver fir (Abies alba Mill.) in Albania.

Terpene composition of needle and cortical oleoresin from lateral shoots were analyzed by GC/MS for four Silver fir (Abies alba Mill.) populations scattered in natural species range in Albania. More than sixty compounds were detected in the needle oleoresin, which was characterized by a high content of alpha-pinene, camphene, beta-pinene, limonene and bornyl acetate. Three monoterpenes, alpha-pinene, beta-pinene and limonene, and two sesquiterpenes, beta-caryophyllene and germacrene D, comprised the majority of cortical oleoresin. The terpene composition differences among the populations that led to the recognition of two chemotypes. The needle oleoresin from the provinces of Puka, Bulqiza and Llogara were characterised by high amounts of beta-pinene, camphene and alpha-pinene and low amounts of limonene, while that from Drenova had high amounts of beta-pinene and limonene. A similar pattern was found in the cortical oleoresin with the exception of camphene that was a minor contributor. Geographical and seasonal variation between the populations was, also, investigated. Multivariate analysis of both needle and cortical oleoresin separated Drenova (southeastern population) from the other sites. When both major monoterpenes and sesquiterpenes were considered four chemical profiles could be attributed. Based on their chemical profiles, the populations can be divided into two groups: Populations with high content of beta-pinene and alpha-pinene but a low content of limonene (Puka, Bulqiza and Llogara), typical of most of A. alba populations in all its distribution range. Population with a high content of limonene and a moderate content of beta-pinene and alpha-pinene (Drenova).

Nuclear protein antigens in autoimmune rheumatic and connective tissue diseases.

Two nuclear antigens, Sm and RNP, that act as markers in Systemic Rheumatic (SRD) and Connective Tissue Diseases (CTD) have been studied with regard to their composition and biochemical properties. RNP antigen appears to be a 10S nuclear RNP particle containing SnRNA. Sm antigen, formerly considered to be a protein, may also contain RNA. Although both antigens are considered to be saline soluble, evidence suggests that they are part of a nuclear structure that is only slowly dissociated under isotonic conditions.