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近年，早期母子接触の有効性が見直される中，母と子の双方に対する効果を期待し，出生直後の正常新生児にカンガルーケアを導入している。そこで，カンガルーケアが母親にどんな良い影響を与えるのかをあきらかにするためにこの研究に取り組んだ。 当院で分娩した母親への郵送アンケート調査や今回の出産で初めてカンガルーケアを行なった経産婦の感想を述べてもらった。その結果より，産んだ実感や感動は，より大きく，しかもカンガルーケアを始めてからは，分娩後早い時期から，また長い時間わが子とともにいたいと希望する母親が増えている。親子の相互作用により，安心感や信頼感が確立されると考えられる。今回の研究から，出生直後のカンガルーケアは母親の感情・行動に良い結果を与えることが分かった。

Cyclic esters, S-esters, and amides of phenyl(thio)phosphonic acid were synthesized to probe the interaction between noncompetitive antagonists of ionotropic gamma-aminobutyric acid (GABA) receptors and their binding site. Some of these compounds competitively inhibited the specific binding of [3H]EBOB, a noncompetitive GABA antagonist, to rat-brain and housefly-head membranes. The trans isomer of the ester bearing a tert-butyl group at the 5-position and a bromine atom at the p-position (5t) was most potent in rat receptors with an IC50 value of 40 nM, while the trans isomer of the S-ester bearing the same substituents (10t) was most potent in housefly receptors with an IC50 value of 55 nM. In both cases, the corresponding amide analogue (12t) was less potent. The potencies of 5t and 12t tended to decrease in the presence of GABA, particularly in housefly receptors, while that of 10t remained unchanged. The rank order of activity in inhibiting [3H]EBOB binding to housefly-head membranes in the presence of GABA (10t > 5t > 12t) was in accord with that of insecticidal activity. S-Ester 10t depressed 10 microM and 300 microM GABA-induced 36Cl- influx into mouse cerebral synaptoneurosomes, whereas ester 5t depressed 10 microM GABA-induced 36Cl- influx but not 300 microM GABA-induced flux. Amide 12t was inactive at both GABA concentrations. These findings indicate that six-membered cyclic phenylthiophosphonic acid derivatives act as noncompetitive antagonists of GABA receptors and suggest that 10t is able to bind to the receptor in the open, desensitized, and closed states, whereas the affinity of 5t and 12t is lower in the open and desensitized states than in the closed state. The derivatives have similar structures except for the heteroatoms at the 1- and 3-positions, so that the heteroatoms may play a unique role when antagonists bring the open state of the GABA-gated channel to the desensitized or closed state.

The duct epithelial cells of rabbit submandibular glands expressed keratin 8, keratin 14, and actin in the supranuclear region, and these cytoskeletal proteins formed ring structures, approximately 1-2.5 microm in diameter. Ultrastructurally, these ring structures were observed as a 'Golgi-associated filament network' surrounding Golgi apparatuses. Double immunofluorescent studies showed that keratin 8 and keratin 14 formed keratin 8/14 filaments, and that these filaments and actin filaments colocalized as components of the Golgi-associated filament network. Our studies suggested that the Golgi-associated filament network maintains the complex structure and location of the Golgi apparatus of the duct epithelium of rabbit submandibular glands. Tubulin was distributed diffusely throughout the cytoplasm of columnar cells, but no special relationship was found between tubulin and the Golgi apparatus.

In rabbit intestinal epithelium, vimentin intermediate filaments are selectively expressed in the M cells of follicle-associated epithelium (FAE). To find intestinal epithelial cells belonging to the M cell lineage, vimentin was detected immunohistochemically in the rabbit small and large intestines. Vimentin-positive columnar cells were scattered throughout the villus epithelium of the small intestine. In their cytoplasm, vimentin was located from the perinuclear region to the cell membrane touching intraepithelial lymphocytes. These cells had microvilli shorter than those of absorptive cells, and the alkaline phosphatase activity of the microvilli was markedly weaker than that of absorptive cell microvilli. Glycoconjugates on the surface of the microvilli were alcian blue positive and periodic acid-Schiff negative. The morphological and histochemical features of these vimentin-positive villus epithelial cells differed from those of adjacent absorptive cells and closely resembled those of the M cells in FAE covering Peyer's patches and solitary lymphatic nodules. These results suggest that the vimentin-positive cells in the villus epithelium belong to the M cell lineage.

Sea urchin spinal ligaments (the catch apparatus) were extracted with glycerin, and electron microscopic observations comfirmed that no cell membranes remained intact after glycerination. We studied the effects of cations (Na(+), K(+), Ca(2+), Mg(2+)) on the mechanical properties of the glycerinated ligaments. Monovalent cations decreased whereas divalent cations increased the viscosity of the ligaments. The ion dependencies were similar to previous results with detergent-extracted holothurian dermis, which suggests that the echinoid ligament shares a similar mechanism for changes in mechanical properties with other catch connective tissues. This provides evidence against the hypothesis of that muscles in the catch apparatus are responsible for the changes in mechanical properties of the ligament. Fine projections cross-bridging collagen fibrils were observed in the glycerin-extracted ligaments as well as in the intact ligaments. They were found in all the ionic conditions studied.

3-Aminopropyl(methyl)phosphinic acid (APMP), a potent agonist of mammalian GABAB receptors, caused prostration in houseflies (Musca domestica L.) on injection into their thoraces, with an ED50 value of 0.42 microgram/fly. The 48-h LD50 values of APMP were estimated to be 0.45 and 5.6 micrograms/fly in the presence and absence of piperonyl butoxide, a mixed-function oxidase inhibitor, respectively. Analogues of APMP, bearing a longer or shorter side chain by a CH2 unit, or a phenyl group in the place of the methyl group, were without effects. In perfusion assays with synaptosomes prepared from the thoracic/abdominal nerve cords of cockroaches (Periplaneta americana L.), 1 mM APMP reduced K(+)-evoked acetylcholine release to 10.4% of the control. These findings indicate that the--physiologically important site of action of APMP, which might be implicated in neurotransmitter release, is present in insect neurons.