A GABAergic habenulo-raphe pathway mediation of the hypnogenic effects of vasotocin in cat

Electrolytic lesions, performed in the lateral habenula of cats, specifically altered the sleep-wakefulness cycle and completely prevented the usual actions of intraventricularly administered vasotocin, which are to induce non-rapid eye movement sleep and to suppress rapid eye movement sleep. These alterations are (i) selectively related to lateral habenula, since similar lesions performed in thalamus 2 mm lateral to lateral habenula, were unable to prevent the actions of vasotocin or to reproduce the sleep alterations observed after habenular lesions, and (ii) reversible, since at eight days after habenular lesions there is a total return to normal of the sleep-wakefulness parameters, and vasotocin is able again to induce its hypnogenic effects. Opposite effects, characterized by an increase in non-rapid eye movement sleep and a decrease in rapid eye movement sleep, could be induced by a short (10 min) electrical stimulation of the lateral habenula, but not if the stimulating electrodes are placed 2 mm more laterally. Picrotoxin, a gamma-aminobutyrate antagonist, injected intraventricularly in normal cats was without any apparent effect on the sleep-wakefulness cycle if administered in a dose of 1 ng, but had sleep-increasing effects when administered in a dose of 100 ng. However, the smaller dose of picrotoxin (1 ng), when administered 15 min before vasotocin, completely blocked the hypnogenic effect of vasotocin. It is suggested that vasotocin acts within the brain by activating a descending gamma-aminobutyrate-containing habenulo-raphe pathway, and that this pathway plays an important role in the induction and/or organization of the sleep-wakefulness cycle.     

Analyses of the cDNA and genomic DNA sequences encoding the luteinizing hormone beta-subunit precursor protein in the rabbit

To examine the molecular basis for efficient induction of superovulation in the rabbit, we determined the cDNA sequences of the luteinizing hormone beta-subunit (LHB) from Japanese White (JW), New Zealand White (NZW), and Dutch-Belted (Dutch) rabbits, and we compared these LHB sequences with those of other mammals. Using 5'- and 3'-rapid amplification of cDNA ends (RACE) with pituitary cDNA libraries, we found that the LHB cDNAs of all three breeds are the same length (523 bp from the 5'-end to the polyA site) and have putative AATAAA polyadenylation signal sequences at nucleotides 504 to 509. Northern blot analysis indicated that the approximately 600-nt mRNA encoding JW LHB is slightly longer than the LHB mRNAs of the other two breeds. The NZW and Dutch rabbit LHB coding sequences are 426 bp long, and their G+C contents are higher (>73%) than those of other mammalian LHBs (<70%). The predicted 141-amino-acid sequences of the JW and NZW LHB proteins are identical, and the Dutch LHB and JW/NZW sequences differ at only two residues. The exon-intron configuration of the NZW LHB gene (three exons and two introns) is similar to that of other mammalian LHB genes, and the sequences of NZW rabbit and other mammalian LHB promoter regions are highly conserved. Phylogenetic analysis of the deduced amino acid sequences of the three rabbit LHB proteins indicated that the rabbit occupies a phylogenetic position between rodents and domestic animals, and is far from humans. The results suggest that LH prepared from rodents or domestic animals, if available, would be a better inducer for superovulation in rabbits than human LH/CG.     

Proximal attachment of long head of biceps brachii to the bicipital tubercle of scapula and its functional significance

Introduction

Lesions affecting the tendon of Long Head of Biceps brachii (LHB) are among the more frequent causes of pain and disability in the region of shoulder joint. Shoulder arthroscopy has shown that there is dual attachment of LHB to the Supraglenoid tubercle (SGT) and glenoid labrum, but the origin from the bony prominence on upper part of dorsal surface of neck of scapula has not been described in the literature reviewed. This bony elevation has been named as “Bicipital Tubercle (BT)”. What is astonishing is the fact that such a prominent BT has been either missed or ignored by earlier workers.