Tetsuro Sakumoto

Noradrenaline innervation of the spinal cord studied by the horseradish peroxidase method combined with monoamine oxidase staining

SummaryThe origin of the spinal cord noradrenaline (NA) has been investigated by means of the horseradish peroxidase (HRP) method, combined with monoamine oxidase staining (Glenner) to identify the NA neurons. Following the injection of HRP to the various levels of rat spinal cord, cervical to sacral cord, A1–3, 5–7 NA neuron groups were labeled with HRP. They showed almost the same distribution pattern regardless of difference in the injected segment. Labeled NA neurons in A6 were concentrated in the ventral division of the locus coeruleus, which continued to the labeled NA neurons in the subcoeruleus area. The HRP positive neurons in the pons outnumbered those of the medulla oblongata. As the NA neurons described above were considered to be the source of NA in the forebrain, such as the hypothalamus and preoptic area, the possibility that the same NA neurons might innervate both the forebrain and spinal cord has been presented.

Afferent fiber connections from lower brain stem to hypothalamus studied by the horseradish peroxidase method with special reference to noradrenaline innervation

SummaryAttempts were made to determine the afferent projections to the anterior hypothalamus including the preoptic area from the lower brain stem by means of the horseradish peroxidase method combined with monoamine oxidase staining to identify noradrenaline (NA) neurons. In addition to this technique, a histofluorescence analysis was performed. NA fibers in the medial part of the anterior hypothalamus were mainly supplied by A1 and A2 NA neuron groups, while the lateral part and periventricular zone received NA terminals from both pontine and medulla oblongata NA neuron groups. Furthermore, the present study indicated that there were direct projections to the anterior hypothalamus from non-noradrenergic neurons in the lower brain stem: nuclei raphe dorsalis, centralis superior, cells in the mesencephalic and pontine central gray matter, nuclei parabrachialis lateralis and medialis, cells around fasciculus longitudinalis medialis.

Circadian feeding rhythm after hypothalamic knife-cut isolating suprachiasmatic nucleus

Abstract Bilateral parasagittal knife-cut between the suprachiasmatic nucleus (SCN) and lateral hypothalamic area (LH) or coronal knife-cut between the SCN and ventromedial hypothalamic nucleus (VMH) resulted in a partial loss of the circadian feeding rhythm in rats; after either operation the rats consumed about 30% of their total daily food intake during the light period. However, after the parasagittal and coronal knife-cuts were made in combination, the circadian feeding rhythm was completely lost (50% food intake during the light period). Rats which lost the circadian feeding rhythm partially or completely showed neither obesity nor anorexia. These findings suggest that there are dual informational pathways from the SCN, possibly between the SCN and LH and between the SCN and VMH, through which circadian time signals generated in the SCN are transmitted to the LH and VMH to drive the circadian feeding rhythm.

Descending projection of the nucleus tegmentalis latero-dorsalis to the spinal cord; studied by the horseradish peroxidase method following 6-hydroxy-DOPA administration.

Descending projection of the nucleus tegmentalis laterodorsalis (TLD) to the spinal cord was investigated using the horseradish peroxidase (HRP) method following the systemic administration of 6-hydroxy-DOPA (6-OH-DOPA). 6-OH-DOPA pretreatment resulted in an intense labeling of the cell group at the laterocaudal portion of TLD after the injection of HRP to the lower segments of the spinal cord. Whereas in untreated rats, cells at the laterocaudal portion of TLD were faintly labeled. Such indirect effect correlated with a reduction in the number of fluorescent catecholamine nerve terminals in the spinal cord after 6-OH-DOPA injection, suggesting that the descending projection from laterocaudal portion of TLD to the spinal cord might be influenced by the catecholamine neurons in the central nervous system.

Implications of assisted reproductive technologies on term singleton birth weight: an analysis of 25,777 children in the national assisted reproduction registry of Japan

OBJECTIVE To evaluate the implications of assisted reproductive technologies (ART) on neonatal birth weight. DESIGN A retrospective study using analysis of covariance and multiple logistic regression analysis of the Japanese ART registry. SETTING Japanese institutions providing ART treatment. PATIENT(S) A total of 25,777 singleton neonates reaching term gestation following ART during the years 2007-2008, with 11,374 achieved through fresh embryo transfers (fresh ET) and 14,403 achieved through frozen-thawed embryo transfers (FET). INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Birth weight. RESULT(S) The mean birth weight after FET was significantly higher compared with fresh ET and all Japanese births (3,100.7 ± 387.2 g, 3,009.8 ± 376.8 g, and 3,059.6 ± 369.6 g, respectively). The risk for low birth weight in FET was significantly lower compared with fresh ET. In fresh ET, ovarian stimulations were associated with about twofold risk of low birth weight compared with natural cycle. Regarding to the duration of embryonic culture, the risks resulting from a shorter culturing time were significantly higher compared with a longer culturing time in fresh ET. CONCLUSION(S) The best method of embryo transfer for fetal growth was FET after extended culturing until blastocyst stage. However, further investigations should be performed to understand the safety of ART treatment.

Fine structure of rat cerebellar noradrenaline terminals as visualized by potassium permanganate 'in situ perfusion' fixation method.

Abstract The fine structure of noradrenaline-containing nerve terminals in the rat cerebellum was investigated by means of modified potassium permanganate fixation, which revealed a number of small cored vesicles in the terminals. In the molecular layer, noradrenaline-containing terminals mainly made a synaptic like contact with tertiary or secondary Purkinje cell dendrites, while in the Purkinje cell layer no direct contact between noradrenaline-containing terminals and Purkinje cell soma was demonstrated in this study. In the granular layer, noradrenaline-containing nerve terminals were found in its superficial part, particularly around the glomeruli. Noradrenaline-containing nerve terminals in the granular layer mostly make a close contact with the dendrites of the granule cells. As well as confirming the noradrenergic input to Purkinje cells, the results show that noradrenaline might directly influence the granule cells.

Ascending and descending components of the medial forebrain bundle in the rat as demonstrated by the horseradish peroxidase-blue reaction

SummaryThe ascending and descending components of the medial forebrain bundle (MFB) were investigated by means of horseradish peroxidase (HRP) with a sensitive substrate. The HRP was injected iontophoretically into the MFB at various levels from the anterior commissure to the posterior hypothalamus. In order to prevent the diffusion of HRP to other brain areas, a double micropipette system was used. The descending components of the MFB are derived from (1) the anterior cingulate area, infra- or prelimbic area, and sulcal cortex, (2) the lateral septal nucleus and diagonal band, (3) the bed nucleus of the stria terminalis, (4) the paraventricular nucleus (5) the substantia innominata, (6) the amygdaloid complex (AM), (7) the ventromedial (VM) and dorsomedial (DM) hypothalamic nuclei, (8) the entopeduncular nucleus and (9) nucleus periventricularis stellatocellularis. The ascending components of the MFB originate in: (1) the medial preoptic nucleus, (2) the nucleus periventricularis stellatocellularis and rotundocellularis, (3) the posterior hypothalamic nucleus, (4) the parafascicular nucleus, (5) the ventral premammillary nucleus, (6) the substantia grisea periventricularis, (7) the lateral habenular nucleus, (8) the VM and DM, (9) the paratenial nucleus, (10) the AM and (11) the arcuate nucleus.

Dopamine decreases release of luteinizing hormone releasing hormone from superfused rat mediobasal hypothalamus

The effects of dopamine hydrochloride (DA) on the releases of LHRH and LH were examined in a serial sequential double chamber perifusion system by perifusing the mediobasal hypothalamus including the preoptic area and/or pituitaries excised from diestrus female rats. DA, perif used at a dose of 4.2 × 10−4 M, significantly (p < 0.05) lowered LH secretion from the pituitary in series with the hypothalamus 40–80% below the preinfusion level, but it had no effect on LH efflux from the pituitary perifused alone. DA also significantly (p < 0.05) reduced the LHRH level 20–40% below the initial level. Perifusion with the DA receptor blocker haloperidol at a concentration of 10−6 M abolished the suppressive effect of DA on LH secretion. These findings indicate that DA suppressed hypothalamic LHRH release, resulting in decrease in LH secretion from the pituitary in diestrus rats.

Detailed pathways of the raphe dorsalis neuron to the cerebral cortex with use of horseradish peroxidase-3,3′ ,5,5′ tetramethyl benzidine reaction as a tool for the fiber tracing technique

MASAYA TOHYAMA, SADAO SHIOSAKA, MASAH[RO SAKANAKA, HIROSHI TAKAG!, EMIKO SENBA, YO[CHI SAITOH, YASUYUK! TAKAHASHI, TETSURO SAKUMOTO and NOBUO SHIMIZU Department of Neuroanatomy, Institute of Higher Nervous Activity, Osaka University Medical School, 3-57, Nakanoshima 4-chome, Kitaku, Osaka and (N.S.) Department of Anatomy, Fujita-gakuen Univer~sity School of Medicine, Toyoake, Aichi (Japan) (Accepted September 13th, 1979)

Specific antibodies to porcine zona pellucida detected by quantitative radioimmunoassay in both fertile and infertile women

The specific radioimmunoassay system was developed for the titration of the antibodies to porcine zona pellucida (ZP) in human sera by using 125I-labeled purified porcine ZP as antigen, which is known to have cross-reactivity with human ZP. The antibodies in human sera were detected in 3 of 11 (27%) women with unexplained infertility, in 16 of 48 (33%) amenorrheic patients, in 4 of 12 (33%) fertile women, and in 3 of 10 (30%) men. Moreover, antibody titers in infertile women were no higher than those in fertile women and in men. These results seem to suggest that the antibodies in human sera that cross-react with porcine ZP may not be an important factor in causing infertility in women.