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Notes: Abstract: At D2 3,4-dihydroxyphenylethylamine (dopamine) receptors in anterior pituitary tissue, magnesium ions shifted receptors to agonist high-affinity states, but decreased the affinity of the antagonist [3H]spiperone. Conversely, sodium ions shifted the receptors to agonist low-affinity states, but increased the affinity of [3H]spiperone. Magnesium is proposed to stabilize the hormone–receptor–guanine nucleotide regulatory protein complex, whereas sodium appears to destabilize this ternary complex. Thus, magnesium and sodium appear to mediate their regulatory effects via a common component at the D2 dopamine-receptor ternary complex.

Notes: Abstract: In comparison with normal controls, hydrocortisone-intoxicated rats (HC rats) had smaller cerebra, lowered 2′,3′-cyclic nucleotide 3′-phosphohydrolase (CNPase) activity, and greatly reduced learning ability. The reduction in cerebral weight and DNA content was considered to be caused by a decrease in the number of proliferating glial cells, because the usual postnatal elevation of thymidine kinase (TK) activity was found to be suppressed in the cerebra from the HC rats. Electron microscopic observation of the pituitary gland revealed that the 5-day-old HC rat contained growth hormone (GH) secretory cells which were fully packed with GH granules, suggesting a disorder in the system which releases GH. In an attempt to promote cerebral development in the HC rats, we administered bovine GH (bGH) to some of the HC rats daily from the day of birth until weaning (HC + bGH rats). In the HC + bGH rats, the cerebral DNA was restored to normal levels and a concomitant increase in TK and CNPase activity was noted. Furthermore, in the brightness discrimination test, whereas the HC + bGH rats attained the learning ability of the normal controls after only 10 sessions, the HC rats were unable to reach an equivalent level even after 25 sessions.

Notes: Abstract: Erythrocyte membrane Na,K-ATPase activity of manic patients was studied. The activity of patients in acute manic phase was higher than that of normal controls, while that of patients in normal phase was not. Even in the same patient, the activity in acute phase was higher than that in normal phase. Mg-ATPase activities did not differ between controls and patients. These findings clearly indicate a possible correlation between change in clinical phase in manic patients and change ot erythrocyte membrane Na,K-ATPase activity.

Notes: Abstract: Although dopamine agonists can recognize two states of the D2 dopamine receptor in the anterior pituitary (Dhigh2 and Dlow2), we examined whether the dopamine antagonists such as [3H]spiperone could recognize these two sites with different affinities. Using up to 30 concentrations of [3H]spiperone, however, we could only detect a single population of binding sites (porcine anterior pituitary homogenates) with a dissociation constant (KD) of 130 pM. When specific [3H]spiperone binding was defined by a low concentration of (+)-butaclamol (100 nM), the apparent density was low. When defined by a high concentration of (+)-butaclamol (10 μM), nonspecific sites became detectable, thus revealing two apparent populations of sites for [3H]spiperone, only one of which was specific for dopamine. Sodium chloride reduced the KD of the single population of specific D2 sites to 64 pM. Guanine nucleotide by itself had no effect on the KD, but enhanced the density by 25%. Since the density-enhancement could be eliminated by extensive washing of membranes, and could be restored by preincubation with dopamine, the nucleotide-induced elevation of D2 density appeared to be a result of the release of tightly bound endogenous dopamine. Thus, monovalent cations and guanine nucleotides appear to have separate regulatory effects on the anterior pituitary D2 receptor that modulate antagonist-receptor interactions. Several maneuvers were used to test whether [3H]spiperone could differentiate between the two agonist-detected subpopulations of sites. Twentyfold different concentrations of [3H]spiperone (47 pM and 1000 pM) were found to label identical proportions of receptors in the Dhigh2 and Dlow2 states as detected by the agonist 6,7-dihydroxyaminotetralin (ADTN), suggesting that spiperone labelled equal proportions of Dhigh2 and Dlow2 sites without differential affinity for them. In addition, competition of spiperone for Dhigh2 sites selectively labelled by the agonist [3H]n-propylnora pomorphine (NPA) had a virtually identical KD for spiperone as did the total D2 receptor population as determined by direct binding studies (75 pM versus 64 pM). [3H]Spiperone also bound to a uniform population of Dlow2 sites induced by preincubation with guanine nucleotide with identical affinity as to the total D2 population. Thus, these data do not support a “reciprocal model’ for the D2 receptor (i.e., antagonist having low affinity for Dhigh2 and high affinity for Dlow2 in a manner reciprocal to agonists). It is therefore concluded from these studies that spiperone recognizes the Dhigh2 and Dlow2 states of the receptor with equal affinity and no evidence is provided in support for reciprocal modulation of antagonist/agonist affinities.

Notes: Performance auditing is a common interest in the Supreme Audit Institutions of the developed countries. In Japan, the Board of Audit (JBA) has been developed and has expanded performance audits since its establishment (1880). In this paper, the methodological and organizational problems which arise according to expansion of performance audits are discussed, based on JBA's experiences. As for methodological problems, a self-development approach should be needed, added to the compliance approach (that is, traditional auditing concept). And as for organizational problems, the function presenting feedback information to the Diet should be put in an important position in government auditing to avoid “unintended effects”.

Notes: Phylogenetic analyses were carried out on 15 strains of Microcystis, with five morphospecies and including two types of phycobilin pigment composition, by sequence determination of the 16S rDNA (16S rRNA gene). All the sequences showed high similarity, in some cases 100% similarity, between different morphospecies and phycobilin types. Derived phylogenetic trees revealed a close relationship between Microcystis strains with and without phycoerythrin. The data show that phenotypes of Microcystis do not necessarily reflect their phylogeny, and that there is a need to reconstruct the present taxonomy at the species level.

Notes: 16S to 23S ribosomal DNA internal transcribed spacer sequences of 47 strains of the genus Microcystis were determined. Derived maximum likelihood and DNA distance trees indicated that Microcystis can be divided into three clusters. The first cluster included toxic and non-toxic strains, the second only toxic ones, and the third only non-toxic ones. The tree topologies were not necessarily correlated with morphospecies distinction or phycobilin pigment composition, and one genotype may have more than one morphotype. Phylogenetic analysis based on intergenic spacer sequences was thought to be effective for understanding relationships among closely related species and strains.

Notes: Abstract The regional, cellular, and subcellular distribution of Thy-1 antigen in rat nervous tissues was investigated with rabbit and anti-rat thymus antiserum. Thy-1 antigen was found most abundantly in the cerebrum, including the cerebral cortical layer, caudate nucleus, thalamus, and hypothalamus, and in the midbrain. It was found in lower amounts in the pons, medulla oblongata, cerebellum, and spinal cord. The content of Thy-1 antigen, however, was low in the retina, cervical sympathetic ganglion, and sciatic nerve, and there was little in the pineal body and adrenal medulla. Thy-1 antigen was present in the neuronal cell-enriched fraction, whereas the glial cell-enriched fraction lacked Thy-1 antigen. In a subcellular fractionation study, Thy-1 antigen was found to occur mainly in the synaptosomal membrane and microsomes and was low in the highly purified myelin fraction. The amount of Thy-1 antigen in the cerebral synaptosomal fraction was much higher than those in the cerebellar synaptosomal fraction. The distribution of Thy-1 antigen among the respective areas within the cerebrum was not significantly different, and it is suggested that Thy-1 antigen may be present evenly in the neuronal membranes of the cerebrum. Based on these results, Thy-1 antigen is considered to represent a useful marker of cerebral neuronal membranes, especially in the synaptic region, regardless of the kind of neurotransmitters.