Effect of lofepramine and other antidepressants on the uptake of 5-hydroxytryptamine and noradrenaline into rat brain monoaminergic neurons

Lofepramine, (N-methyl-N-[4-chlorobenzoylmethyl]-3-[10,11-dihydro-5H-dibenz(b,f)-azepin-5-yl]-propylamine hydrochloride), is a new antidepressant with low toxicity and no peripheral anticholinergic activity. Its effect on 5-hydroxytryptamine (5-HT) and noradrenaline uptake into rat brain monoaminergic neurons was studied and compared with that of other antidepressants, particularly with that of imipramine and desipramine. Lofepramine inhibited both 5-HT and noradrenaline uptake into synaptosomal fractions in vitro but was 4 times more potent in inhibiting noradrenaline than 5-HT uptake, indicating the effect resembles that of desipramine. Noradrenaline uptake was also preferentially inhibited in synaptosomes from brain of rats treated previously with lofepramine or desipramine (i.p.). Pretreatment with SKF 525A (i.p.) did not diminish the effect of lofepramine, but rather potentiated it. Therefore it is suggested that the formation of desipramine is not necessary for lofepramine to exhibit, the effect on amine uptake in vivo. Both lofepramine and desipramine inhibited intraventricular noradrenaline uptake into synaptosomes without any effect on 5-HT uptake. These results suggest that lofepramine is qualitatively similar to desipramine with respect to preferential inhibition of noradrenaline uptake into central noradrenergic neurons.

Vascular supply to the organ of corti in man

The capillary distribution in the basilar membrane and the osseous spiral lamina was studied in 40 human temporal bones. The capillaries were made visible using a histochemical technique for demonstrating alkaline phosphatase activity. High tone sensorineural hearing loss can be explained by capillary distribution, length of a segment in the outer spiral vessel and the distance between the inner and the outer spiral vessels in different cochlear turns.

Estrogen receptor and endocrine responsiveness in Japanese versus American breast cancer patients

We have compared the incidence of estrogen receptor (ER) in breast tumors and its clinical correlation with responses to endocrine therapies in Japanese and American patients. There was no correlation between tumor histopathology and the presence of ER, and the ER values in primary and metastatic lesions from the same patients were similar in most Papanese cases. Japanese patients with low and high plasma estradiol levels had identical incidences of ER-positive tumors. The correlation between tumor ER and response to endocrine therapy is similar between Japanese and American patients. The incidence of ER-positive tumors is higher in postmenopausal American patients in both primary and metastatic lesions. It is possible that the reported increase in tumor lymphocyte infiltration in Japanese patients may explain this difference. The reported 5-year survival advantage of Japanese breast cancer patients cannot be explained by differences between the two populations in the response to endocrine therapy for advanced disease.

Sudden deafness. A histopathological study

Histopathological studies were performed in the temporal bones from a 77-year-old woman who had bilateral sudden deafness 31 years before her death. The common findings in both cochleas were atrophy of the organ of Corti and stria vascularis, and degeneration of the tectorial membrane. Pathology of the tectorial membrane consisted of atrophy and droplet formation of the middle and marginal zones. In one area, an atrophied tectorial membrane was lifted up by a mass on the limbus. The saccular wall in the left temporal bone was ruptured. There was no pathology in the vascular system in the labyrinths except for moderate degeneration of sensory epithelium. The pathogenesis of sudden deafness was discussed in the light of the present findings. Alteration of the tectorial membrane seemed to be the main factor as a possible cause of sudden deafness. Histopathological findings were reviewed from the literature.

Nerve fibers in the human organ of Corti

In the human cochlea, the following characteristics of nerve fiber arrangements were observed. 1. Where there was only the basilar fiber in the tunnel of Corti, the internal and tunnel spiral bundle were not observed. In such cases, the number of nerve fibers in the external spiral bundle was small. 2. In the tunnel of Corti, the basilar fibers (afferent) took a course at the base and crossing the tunnel slanting to the basal end. 3. The medial fibers were present with the internal spiral bundle and tunnel spiral bundle. These fibers are possibly efferent. 4. The external spiral bundle increases its fiber count when internal and tunnel spiral bundles were present in the organ of Corti. 5. The external spiral bundle was composed of the basilar and medial fibers. The former were less and the latter much more numerous in the bundle. 6. 85-90% of the afferent fibers went to the internal hair cells, while the remainder went to the external hair cells. 7. The nerve fibers were found in the organ of Corti lateral to the external spiral bundles. The fibers were running in the Hensen's and Claudius' cell area. 8. In some cases medial fibers showed a torpedo-like deformity in the tunnel of Corti. When this was observed, it was found distributed throughout the entire cochlea. Hearing disorders due to this pathology of the efferent fiber was suggested.

Estrogen receptor in breast cancer of the Japanese

The estrogen receptor was assayed, using the 2,000g supernatant and dextran-coated charcoal method, in 243 tissue samples from human breast cancer, benign breast diseases, macroscopically normal breast tissues, normal uterine myometrium, and uterine myoma. The estrogen receptor was found to be positive in 52.1% of 98 primary breast cancer and in 54.1% of 24 metastatic tumors. The receptor in the breast cancer was found to be similar to that in normal uterine myometrium in the binding character; that is, the dissociation constant of 10(-9) approximately 10(-11) M and number of binding sites of 0 approximately 2,800 fmol/mg protein. There was no correlation between the presence of the receptor and some clinical factors such as menopausal status, age of the patient, urinary 17-ketosteroid excretion, clinical stage of cancer, tumor size, positive or negative axillary lymph node metastasis, histological type, metastatic site of the cancer, or disease-free interval. The estrogen receptor appeared to be retained by metastasis of cancer, and this may lead to the use of the receptor assay with mastectomy specimens for the prediction of response to hormonal therapy in future recurrence of malignancy. Furthermore, it may be possible by this assay to select patients suitable for adjuvant therapy with hormones at the time of mastectomy. A good correlation was found between the presence of the receptor and response to the major endocrine ablation therapy in patients with advanced or metastatic breast cancer. When the receptor was negative in the cancer tissue, the change of response to the endocrine therapy was minimum. On the other hand, if the cancer contained the receptor, approximately 60% of the patients with metastatic or advanced breast cancer responded well to the major endocrine ablation therapy. Thus, the estrogen receptor of breast cancer in Japanese patients appears to bear a close resemblance to that reported in Western patients in its incidence and the correlation to some biological characteristics of the cancer.

[Peripheral nerve disease associated with acute renal failure due to bromate poisoning]

A case of 21 year old male with neuropathy caused by renal insufficiency was present. He had taken bromate (mixed powder of potassium bromate and sodium bromate) for the purpose of suicide and suffered from acute renal insufficiency and hard of hearing. Renal dysfunction improved gradually by peritoneal dialysis and hemodialysis. However, on the 32th day after the onset, burning pain appeared in the bilateral feets. Following this, he began to complain of the disturbances of superficial and deep sensory below the ankle jerks and the weakness of his toes. Considering the clinical features, we supposed that the disturbance of the peripheral nerve was caused by uremia due to taking bromate. N. suralis was biopsied on the 80th day after the onset and examined electron microscopically. Electroscopical findings was as follows. Degeneration of the Schwann cells and irregularity or destruction of the myelin sheaths were observed. The axoplasm of the myelinated nerve fiber were relatively preserved as compared with the changes of the myelin sheaths. In the unmyelinated nerve fibers, cavity formations were observed. The findings of regeneration were not observed. From the electron microscopical findings, we speculate that the changes of the Schwann cells and the myelin sheaths are primary resulting from the disturbance of the metabolism of the Schwann cells. We speculate that anemia and hypoproteinemia caused by bromate disturbed regeneration.

Follow-up study of left suprarenal to inferior mesenteric venous shunt for advanced breast cancer

Major endocrine ablation therapy was carried out in 133 patients with advanced breast cancer. Of 40 patients undergoing left suprarenal to inferior mesenteric venous shunt with bilateral oophorectomy and right adrenalectomy, 16 cases (40 per cent) had an objective response. The mean postoperative survival of the patients with a positive response, those showing some response and those who failed to respond was 35-8, 26-5 and 8-8 months respectively. Thus, the results of the present procedure are comparable to those of adrenalectomy. No replacement therapy with corticoids was necessary. An increase in the response rate and extension of the survival time can be expected with the addition of postoperative long term maintenance therapy with chemotherapeutic agents and androgens.

Effects of synthetic progestational steroids on liver and serum lipids in rats

Effects of norethisterone (NT) purified norethisterone (pure NT), norethynodrel (NE), medroxyprogesterone acetate (MAP), chlormadinone acetate (CMA) and desoxycorticosterone acetate (DOCA) on serum and liver lipid levels and serum lipoproteins were examined in both intact and estradiol-treated male rats. NT and NE caused a decrease in serum cholesterol and phospholipid levels, an increase in liver cholesterol level, no significant change in triglyceride levels of both serum and liver, with a significant change in serum lipoprotein patterns; a decreased in alpha- and beta-lipoproteins and a marked increase in pre beta-lipoprotein. Pure NT decreased serum cholesterol without causing any change in lipoprotein pattern. MAP, CMA and DOCA causee almost no effect on lipid levels in serum and liver, but CMA and DOCA increased alpha-lipoprotein and decreased beta- and pre beta-lipoproteins. An acute treatment with estradiol caused a decrease in alpha- and beta-lipoproteins and an increase in pre beta-lipoprotein with a decrease in serum lipid levels and an increase in liver lipids. By contrary, a chronic treatment with a marked hypercholesterolemia. This increase of alpha-lipoprotein in estradiol-treated rats was prevented by NT and NE, not affected or rather decreased by MAP but further increased with CMA and DOCA. These data suggest that the effects of synthetic progestational steroids on lipids are classified into two groups, 19-nortestosterone derivatives and 17alpha-hydroxyprogesterone derivatives including DOCA. The former caused a decrease in serum lipid levels with an increase of pre beta-lipoprotein and adecrease of alpha-lipoprotein. The latter caused almost no change or a slight increase in serum lipid levels with a decrease in pre beta-lipoprotein and an increase in alpha-lipoprotein, though it was not found in MAP.

Possible retention of the estrogen-binding capacity after endocrine ablation therapy in the rat and human breast cancer

The estrogen-binding capacity of the regrowing tumors after endocrine ablation surgery was estimated in the rat and human breast cancer. All of 4 tumors that had not had the estrogen receptor before oophorectomy did not show the estrogen-binding capacity after the procedure, in the mammary cancer in the Sprague-Dawley rat induced by 7,12-dimethylbenz[a]anthracene, whereas all the 4 tumors that had the receptor before the procedure showed the binding capacity after oophorectomy. In 4 patients who had been subjected to the major endocrine ablation therapy because of metastatic breast cancer with effective response, the secondary metastatic deposits of cancer showed the estrogen-binding capacity long after the endocrine ablation. The fact that regrowing tumors after complete or partial regression of initial tumors by endocrine ablation retain the estrogen receptor seems to be contradictory to the classical concept of autonomy in recurrence of the breast cancer after hormonal manipulation.

Regional changes in monoamine content and uptake of the rat brain during postnatal development

Regional norepinephrine (NE), dopamine (DA) and serotonin (5-hydroxytryptamine, 5-HT) contents in the developing rat brain were estimated. The rate of increase in NE content was the highest in diencephalon, followed by the lower brain stem, limbic-striatum, neocortex and cerebellum. With postnatal aging, DA concentration increased markedly in limbic-striatum, slightly in the neocortex and negligibly in other regions. In each region except cerebellum, 5-HT content increased gradually but the rate of increase in diencephalon was relatively high. Comparison of the kinetics of high affinity uptake of L-[3H]NE and [3H]5-HT between the neonatal and the adult brain indicated that Km values of L-[3H]NE and [3H]5-HT uptake were 2.9 X 10(-7) M and 1.7 X 10(-7) M respectively in neocortex, diencephalon and lower brain stem and 4.3 X 10(-7) M and 2.3 X 10(-7) M in limbic-striatum in the neonate as well as in the adult. Vmax values of both amines uptake differed regionally and the values in the neonate were lower than those in the adult in all regions. Limbic-striatum showed a higher Vmax value than other regions in uptake of both amines. These results suggested that innervation of monoaminergic neurons in the brain progressed with increasing age, that projections of both NE and 5-HT neurons were relatively high into hypothalamus and limbic-striatum and that DA neuron projections concentrated at striatum. Although the brain, except for limbic-striatum, showed neither regional nor developmental differences in affinity of L-[3H]NE and [3H]5-HT to synaptosomes, the density of nerve terminal of both monoaminergic neurons increased in all regions of the brain during postnatal development. In limbic-striatum, higher Km and Vmax values of both amines, uptake suggest the existence of both amines' uptake into DA terminal to some extent.

Regional changes in brain catecholamine content following administration of guanethidine to neonatal rats

Norepinephrine(NE), dopamine(DA) and serotonin(5-hydroxytryptamine, 5-HT) contents were estimated in the different regions of the developing rat brain following guanethidine injection at the neonatal period for the purpose of determining the influence of guanethidine on development of the monoamine neuron in the brain. Despite a nonsignificant change in the weights of all regions of the brain, guanethidine caused a significant reduction of NE content in the limbic-striatum at day 7 and 30 and an increase in mesencephalon-ponsmedulla at day 30. DA concentration in the limbic-striatum at day 7, 14 and 30 and in the neocortex at day 7 showed a decrease with guanethedine treatment. The change in 5-HT content was not induced with guanethidine in all regions and all days examined. These results suggest that guanethidine, crossing the blood-brain barrier at the neonatal stage, induced the degeneration of the nerve terminals and "collateral accumulation" of catecholamines in the central NE and DA neurons.

Lack of correlation between the presence of estrogen receptor and histological type of mammary cancer induced by 7,12-dimethylbenz[alpha]anthracene

The relation between the histological type and the presence of estrogen receptor or response to oophorectomy was investigated in the mammary cancer induced by 7,12-dimethylbenz[alpha]anthracene in Spargue-Dawley rats. The estrogen receptor was present in 75.0% (3/4) of poorly differentiated cancer and in 62.5% (10/16) of well-differentiated cancer. The histological degree of differentiation or grading of the rat mammary cancer did not affect the presence of the estrogen receptor or response to oophorectomy. In contrast, there was clearly a good correlation between the presence of the receptor and response to oophorectomy.