The effects of hypothalamic extracts and TRH on the growth and hormone production of GH3 cells in culture

Hypothalamic factors were tested for their effects on the production of hormones and the growth of GH3 cells, cloned rat pituitary cells producing prolactin (Prl) and growth hormone (GH). Hypothalamic extracts (HE) (0.05 mg/ml) and TRH (0.3 microM) stimulated the synthesis of Prl to levels of 306% and 360%, respectively, of the control culture in a medium containing 0.5% foetal bovine serum (FBS) during a 24 h incubation. They did not affect the rate of GH production. The thymidine uptake was suppressed to 57% and 46% of the control by the addition of HE and TRH, respectively. They also inhibited the growth of GH3 to 70% and 74% of the control culture during an 8-day incubation period. On the other hand, LRH affected neither the rate of hormone production nor the thymidine uptake. Somatostatin suppressed the synthesis of Prl and GH, but it did not affect the incorporation of thymidine into the cells. The gel filtration studies of HE revealed that the inhibitory effects of HE on the thymidine uptake were dependent on two substances, TRH and an unknown factor(s) of high molecular nature. The relationship between hormone synthesis and DNA synthesis will be discussed on the basis of the TRH-induced effects on Prl production and DNA synthesis in GH3 cells.

An improved fixation technique for maintaining the fine structure of the nuclear zone of neonatal mouse lens

The fine structure of the nuclear zone of neonatal mouse lenses can vary considerably according to the fixation used. When normal neonatal mouse lenses are fixed in a commonly used chilled glutaraldehyde solution, the nuclear zone develops a grossly visible opacity, and irregular sized protein granules appear in the subsequent sections. Similar artifacts of aggregated irregular sized protein granules appear when cataractous mouse lens are conventionally processed. These artifacts can be avoided by soaking the lens in 0.15 M reduced glutathione solution for 10-15 min before fixation in a phosphate buffered 2% glutaraldehyde solution (pH 7.4) at 27-35 C. Normal lenses treated in this manner maintain translucency in the nuclear zone throughout the fixation-embedding procedure, and the resulting sections show finely uniform granularity with the cell membrane well preserved. Similarly processed nuclear portions of cataractous lenses of Nakano mice show uniformly aggregated protein granules, measuring about 350A in diameter. The cell membranes in the cataractous zone are also not interrupted.

A case of idiopathic fatty liver detectable only by ultrasonography

A 40-year-old man was diagnosed as fatty liver according to our ultrasonographical criteria for fatty liver, i.e., liver-kidney contrast in the ultrasound mass screening of the liver, biliary tract and pancreas. He lacked any signs or symptoms, nor any known causes of fatty liver, i.e., obesity, diabetes, hyperlipidemia, ingestion of alcohol or drugs. Liver biopsy of this patient revealed fatty change of about 50% of the hepatic lobules. It has been difficult to suspect the presence of latent fatty liver which lacked both the abnormality in the liver function test and hepatomegaly, and even impossible when it lacked any risk factors. In the future as the ultrasonography becomes more generally used as a primary screening examination, "idiopathic latent fatty liver", like this patient, will be more frequently found and this, in turn, will contribute to the progress of the epidemiology and etiology of fatty liver.

Ambiguous motoneurons discharging synchronously with ultrasonic vocalization in rats

Unit discharges associated with ultrasonic vocalization were recorded from the rat medullary region including the nucleus ambiguous (NA). Three types of units were distinguished: ultrasound-related (US), expiration (EXP) and inspiration (INSP) units. Both US and EXP units discharged with tonic bursts mostly prior to ultrasounds. US units were silent during respiration while EXP units discharged synchronously with expiration. During ultrasonic vocalization INSP units suppressed their discharges which were otherwise synchronized with inspiration. Histological examination revealed that US and EXP units were recorded from the ventral division of the NA and the adjacent medullary region where the NA contained large cells and the adjacent region consisted of small cells. These results suggest that both US and EXP units are NA motoneurons responsible for ultrasound emission. EXP units were always supplied with respiratory afferents while US units were not.

Ultrasonographical diagnosis of fatty liver: significance of the liver-kidney contrast

In order to investigate the reliability of ultrasonography in the diagnosis of fatty liver, retrospective evaluation was made of abdominal echograms in 45 patients with various diffuse liver diseases who underwent liver biopsy within 2 weeks after the ultrasound study. Instead of the well-recognized but subjective diagnostic criterion, i.e. the bright liver pattern, liver-kidney contrast is proposed as a new criterion. The liver-kidney contrast is based on the brightness of the liver in comparison to the renal parenchyma where fatty change seldom occurs. Combination of this liver-kidney contrast with two other well-known ultrasonographical findings of fatty liver, vascular blurring and deep attenuation, enables us to grade fatty change semiquantitatively. When fatty change of over 30% in the hepatic lobule was adopted as the definition of fatty liver, the satisfaction of both liver-kidney contrast and vascular blurring presented an ultrasound diagnostic criterion for fatty liver, with sensitivity of 83%, specificity of 100%, and an accuracy of 96%.

Effects of TRH on cell proliferation of rat pituitary cells (GH3)

Chronic treatment (more than 3 d) of GH3 cells, cloned rat pituitary cells producing prolactin, with 100 nM TRH resulted in a 41% reduction in the rate of cell growth in a medium containing 0.5% fetal bovine serum. These effects of TRH appeared both in the medium containing a higher concentration of serum and in that containing six growth factors, i.e. insulin, transferrin, parathyroid hormone, fibroblast growth factor, triiodothyronine, and multiplication-stimulating activity (MSA) instead of serum. TRH stimulated prolactin production by GH3 cells in a dose-dependent manner both in the serum-supplemented and serum-free media. On the other hand, TRH, at 1 nM, elicited a 130% stimulation in the cellular growth, whereas, at concentrations of more than 10 nM, it inhibited the growth significantly. In the defined culture system, it was demonstrated that TRH stimulated prolactin production in the presence or absence of six growth factors, whereas its inhibitory effects on cellular growth appeared only in the presence of MSA regardless of the presence or absence of the other five factors. Furthermore, it was shown that a dose-dependent stimulatory effect of MSA on the growth of GH3 cells was suppressed by TRH. TRH exhibited only a stimulatory effect on cellular growth in the medium containing the five factors other than MSA. In conclusion, TRH could inhibit cell growth of GH3 in the presence of MSA in the defined medium or MSA-like factor(s) in the serum-supplemented medium.

The interaction of non-transforming Epstein-Barr virus (EBV) with cell-associated EBV DNA in superinfected lymphoblastoid cell lines

Two human lymphoblastoid cell lines were established by the transformation of human cord-blood lymphocytes with transforming Epstein-Barr virus (EBV). One cell line (HLB-R1) was established with EBV obtained after the superinfection of Raji cells with HR-1 EBV and the other (HLB-Bl) was established from B95-8 EBV-infected human cord-blood lymphocytes. Both the HLB-R1 and HLB-B1 lines were susceptible to superinfection with HR-1 EBV. We found that EBV DNA was replicated in the superinfected cell lines and that transforming EBV was produced in both the HLB-B1 and HLB-R1 cells. The average titer of transforming EBV obtained in the HR-1 EBV superinfected HLB-B1 and HLB-R1 cell lines was 10(4) transforming units (TU)/ml, whereas the average titers of transforming EBV obtained by the superinfection of Raji cells was 10(1) TU/ml. Epstein-Barr virus capable of inducing early antigen (EA) in superinfected Raji cells (lytic virus) was not detected in any transforming virus preparation. Restriction enzyme digestion patterns of virus DNA isolated from HR-1 and B95-8 cells, as well as from superinfected cells, were compared. The EBV DNA that was replicated in the superinfected HLB-R1 and HLB-B1 cell lines showed a more complex pattern. Our data suggest that recombination between input HR-1 EBV DNA and latent cell-associated EBV DNA occurs. Presumably this recombination results in a change in the biological properties of the newly synthesized virus.

Diurnal fluctuation of blood ammonia levels in adult-type citrullinemia

A 48-year-old man, who was diagnosed as adult-type citrullinemia by quantitative estimation of urea cycle enzymes in the liver, showed a regular nocturnal rise of blood ammonia level. In order to elucidate the mechanism of diurnal fluctuation of blood ammonia level, the patient was put into fasting state for four days. The blood ammonia level rose at the night of the first fasting day even though no food was taken, then it decreased gradually and reached the lowest level in the morning of the third fasting day. Intravenous administration of amino acids mixture under the same starved condition gave rise to a significant elevation of blood ammonia level. Based on these results, it was concluded that hyperammonemia of adult-type citrullinemia could result from the accumulation of free ammonia which was produced from the catabolism of amino acids absorbed from the small intestine and surpassed the urea synthesis of defective urea cycle to flood into the blood. Furthermore, the rise of blood ammonia level at the night of the first fasting day suggested that the circadian rhythm of amino acid-carbohydrate metabolism might superimpose on the process mentioned above.

Ambiguus motoneurons discharging closely associated with ultrasonic vocalization in rats

Unitary discharges closely associated with ultrasound were recorded from the nucleus ambiguus (NA) and adjacent medullary regions in rats. Two main types of units were distinguished: one firing in tonic bursts against little or no background activity prior to ultrasound emission, and the other remaining silent during ultrasound. Tonic burst units in NA are considered as motoneurons which are essential for ultrasound vocalization since lesions including NA completely abolished its production.

Computed tomography in the diagnosis of fatty liver: total lipid content and computed tomography number

Fifty-three histologically proved cases of various diffuse liver disease were studied for their computed tomography numbers (CTN). The machine used was Ohio Nuclear's Delta Scanner 50FS type and CTN was expressed by the Hounsfield unit (H). Mean CTN in each group was as follows: 66.6 +/- 2.6 H in normal control (N), 63.3 +/- 6.0 H in chronic hepatitis (CH). 61.8 +/- 7.0 H in liver cirrhosis (LC), and 44.4 +/- 10.6 H in fatty infiltration (FI). There were no significant differences among them except FI group. As N group were all above 60 H and CH and LC groups were all above 50 H, CTN below 60 H suggests chronic liver disease or fatty infiltration and CTN below 50 H strongly suggests fatty infiltration. In eleven cases where total lipid content of the liver could be be biochemically determined by the sulfo-phospho-vanillin reagent, a relation of total lipid content to CTN was studied. As a result, a significant correlation existed between them (r = -0.89; p less than 0.001). If the diagnostic criterion of fatty liver was set at total lipid content above 100 mg/g wet liver, CT criterion was estimated at CTN below 48 H from the regression formula.

Identification of ultrasonic vocalization substrates determined by electrical stimulation applied to the medulla oblongata in the rat

The aim of the present investigation was to identify the neural structures, within the rat medulla, that are responsible for rodent ultrasound production. Sound producing substrates were found to be located in the reticular formation and some cranial nerve nuclei as well as several other nuclei situated in the lateral and dorsomedial portions of the medulla. To estimate the degree of involvement in the generation of ultrasound signals, the sound response latencies were measured for each structure. The lateral reticular nucleus and the facial nucleus showed latencies that were significantly shorter than those for other nuclei, and they were assumed to have a primary part in rodent ultrasound production. Audible sounds of considerably longer latencies were produced exclusively by stimulation of the trigeminal spinal tract nucleus. No ultrasounds could be obtained in this region. These results were discussed in terms of innervations of the facial and laryngeal musculature by the specific neural structures. Present results were also discussed with reference to the roles of the bulbar monoaminergic neurons projecting to the spinal cord and the role of ascending nociceptive pathways.

Collagenolytic enzyme activity in human ovary: an ovulatory enzyme system

Collagenolytic enzyme activities presumed to play an important role in ovulation were investigated in the human follicular apex, base, and granulosa cell layer throughout the ovarian cycle. Those analyzed were human ovarian collagenase, 2,4-dinitrophenyl-Pro-Gln-Gly-Ile-Ala-Gly-Gln-D-Arg-OH peptidase, N-carbobenzoxy-Gly-Pro-Gly-Gly-Pro-Ala peptidase, and alpha-N-benzoyl-DL-arginine beta-naphthylamide hydrolase. Collagenase activity was also measured in human granulosa cell cultures. The activities of all four enzymes showed a marked preovulatory decrease in the apex. The activities in the apex were slightly higher than those in the base throughout the ovarian cycle. However, the activities in the granulosa cell layer and collagenase activity in the granulosa cell cultures increased toward preovulation and decreased after ovulation. These findings suggest that collagenase is synthesized in the granulosa cells maximally at preovulation and is consumed in the follicular apex at the same time, resulting in collagen degradation and disruption of the follicular wall in collaboration with other collagenolytic enzymes investigated here.

[DNP-peptidase activity in the rabbit ovary (author's transl)]

To examine the possible roles of collagenolytic enzymes in the follicular wall at ovulation, we measured in rabbit ovaries collagenolytic enzymes by using synthetic substrates, DNP-Pro-Gln-Gly-Ile-Ala-Gly-Gln-D-Arg OH supposed to be specific for vertebrate collagenase. Our results clearly demonstrated that DNP-peptidase activity existed, with its optimal pH7.6-pH7.8 in rabbit ovarian follicles. DNP-peptidase activity steadily increased for nine hours following the hCG injection. After nine hours of enzyme activity decreased sharply until about the tenth hour, at which time ovulation had occurred. This pattern of enzyme activities indicates that the DNP-peptidase was consumed for degradation of collagen fibers. After collagen fibers have been completely degraded, this enzyme was increased again. These changes of DNP-peptidase activities at ovulation were similar to cathepsin B1 activities with its optimal pH6.0. It is concluded that DNP-peptidase could be one of ovulatory enzymes in the rabbit.

Pleiotropic expression of Epstein--Barr virus DNA in human epithelial cells

We have attempted to establish a system that can be used to study the association of Epstein--Barr virus (EBV) with epithelial cells. Attempts were made to transfect human carcinoma cells with EBV DNA. Successful transfection was confirmed by the expression of EBV-specific early antigen (EA), virus capsid antigen, and the presence of virus DNA. The transfecting preparation contained a mixture of EBV and cellular DNA extracted from two producer cell lines, P3HR-1 and AG-876. Our data suggest that virus DNA obtained from the P3HR-1 nontransforming, EA-inducing strain of EBV was lytically expressed in the epithelial tumor cells. The DNA derived from AG-876 cells, which produce a transforming, non-EA-inducing strain of EBV, also produced a lytic infection.

Treatment of adult-type citrullinemia with administration of citrate

A 48-year-old man who showed a regular diurnal fluctuation of blood ammonia level was diagnosed as adult-type citrullinemia with quantitative estimation of plasma amino acids and urea cycle enzymes in the liver. The restriction of daily protein intake less than 50 g and oral administration of lactulose had no effect on the blood ammonia level. The efficacy of four amino acid solutions which had been used in order to improve the hepatic encephalopathy was compared each other in this case. Glutamate-arginine mixture had the same effect as glutamate solution in lowering the blood ammonia level, and glutamate was thought to be essential. Also, oral administration of citrate showed a remarkable effect almost comparable to intravenous administration of glutamate. Analysis of plasma amino acids 3 hr after citrate administration demonstrated an increase in glutamate and a decrease in citrulline. These observations suggest that a metabolic pathway of citrate-alpha-ketoglutarate-glutamate-glutamine takes part in disposing free ammonia in the blood.

The midbrain central gray substance as a highly sensitive neural structure for the production of ultrasonic vocalization in the rat

To test whether there were any functional differences between the central gray substance (PVG) and other neural structures for the production of ultrasonic vocalization in the rat, an electrical stimulation experiment was systematically undertaken in diencephalic and mesencephalic tegmental regions. The sound production sensitivity to electrical stimulation was the highest in PVG. This suggested that the periventricular fiber system of Schütz's bundle might be a possible neural structure underlying sound emission in the rat.

[Activity of vertebrate collagenase in the human ovary (author's transl)]

Participation of collagenolytic activities in the ovulatory process had been recently studied in the experimental animals, though their existence in the human ovary remains obscure. In the previous report, we demonstrated the collagenolytic activity by using synthetic substrates N-carbobenzoxy-Gly-Pro-Gly-Gly-Pro-Ala and the cathepsin B1 activity in human ovarian follicles. To investigate the activity for degradation of native collagen in the human ovary, we used 14C-labeled collagen prepared from young rat skin in the present study. Collagenolytic activity for synthetic substrate DNP-Pro-Gln-Gly-Ile-Ala-Gly-Gln-D-Arg OH supposed to be specific for vertebrate collagenase was also measured. Our results clearly demonstrated that there existed vertebrate collagenase activity and the collagenolytic activity measured by using DNP-peptide in the human ovarian follicles. The correlation coefficient between both enzymatic activities was 0.56. The DNP-peptide-degrading activity seemed to partly represent the collagenolytic activity from vertebrate collagenase. It was concluded that vertebrate collagenase besides collagenolytic activities did exist in the human ovary and they seemed to be involved in the degradation of collagen fibers in the follicular apex at the time of ovulation.

[A cytochemical study of acid-phosphatase activity in follicular granulosa cells of human ovaries (author's transl)]

In order to clarify the nature and possible roles of lysosome-like granules observed electronmicroscopically in the granulosa cells of human preovulatory follicles, lysosomal activities in human preovulatory granulosa cells were investigated ultrastructurally by staining a marker enzyme acid phosphatase with modified Gomori technique. In the granulosa cells of follicles 10 approximately 15 mm in diameter, acid phosphatase reaction products were seen only in the Golgi apparatus. In follicles around 20 mm in diameter with extremely thin apical walls, granulosa cells with abundant nexuses and steroidogenic organelles (sER, large spherical mitochondria with tubular cristae and lipid-droplets), had many lysosome-like granules in the perinuclear regions and/or close to lipid droplets. Acid phosphatase reaction products were observed mainly in these granules, and infrequently in Golgi apparatus. These morphological results not only identify such granules as lysosomes, but also indicate that the granulosa cells are rich in the lysosomal activity. Possible roles of lysosomes in preovulatory granulosa cells deduced from the present results are as follows, 1) a role in steroidogenesis or in steroid-secretion, 2) an involvement in the ovulatory process with their proteolytic enzymes.

[Activities of collagenolytic enzymes in the human ovary (author's transl)]

To elucidate the mechanisms of follicular rupture at ovulation in human, activities of collagenolytic enzymes were measured in the human follicles at various stages of development by using two kinds of synthetic substrates, alpha-N-benzoyl-DL-arginine-2-naphthylamide HCl and N-carbobenzoxy-glycyl-prolyl-glycyl-glycyl-prolyl-alanine. The result clarified that human ovaries did have two kinds of collagenolytic activities, one cathepsin B1 with its optimal pH 6.0, the other neutral collagenase with its optimal pH 7.5. To examine the subtle changes of these enzymatic activities in the follicles during ovulatory processes, the follicle wall was dissected into three parts, namely, the granulosal layer, the apical wall and the basal wall without the granulosal layer. Activity of neutral collagenase presented a continuous increase in the follicular wall, while in the granulosal layer its gradual depletion was observed. Cathepsin B1 revealed a significant drop of its activity in the apical wall around a preovulatory period. These results indicate an involvement of collagenolytic enzymes in the human ovulatory process.

Ovulatory changes in the wall at the apex of the human Graafian follicle

The apical wall was studied ultrastructurally in 16 human follicles at various stages of development. In the theca externa and tunica albuginea at the apex of growing follicles, fibroblasts with little cytoplasm and abundant collagen fibres were observed. In the mature follicles, the fibroblastic cytoplasm was well developed, rich in lysosome-like granules and contained peripheral multivesicular structures. Intercellular collagen fibres were sparse. It is suggested that the collagen fibres are digested by the content of lysosomal granules and multivesicular structures, thus aiding follicular rupture.

[An ultrastructural study of ovulatory changes in stromal tissue of the follicular apex in the human (author's transl)]

To elucidate the mechanism of follicular rupture at ovulation in human, ultrastructural changes of stromal tissue of the follicular apex during follicular growth and ovulation were studied by focusing on the collagen and fibroblasts in the stroma. Sixteen ovaries were obtained from women at their thirties who underwent the abdominal hysterectomy for gynecologic diseases. From follicles at various stages of development, apical portions were excised and processed for electronmicroscopy. At the apex of growing follicles, fibroblasts with poor cytoplasm and abundant collagen fibers among them were observed in the layers of tunica albuginea and theca externa. At the preovulatory follicles, fibroblasts had rich cytoplasm containing lysosomal granules and multivesicular structures and intercellular collagen fibers were rather sparse. These lysosomal granules and multivesicular structures in the fibroblasts were much conspicuous in the theca external layer of preovulatory and post-ruptured follicles and collagen fibers among these fibroblasts were almost disappeared. It seems that these intercellular collagen fibers and ground substance were digested by the content of lysosomal granules and multivesicular structures.

[The vasopressor role of ADH in the maintenance of blood pressure in experimentally hypertensive rats (author's transl)]

In order to investigate the vasopressor role of ADH in the regulation of blood pressure, passive immunization experiments with an antibody to AVP were carried out in experimentally hypertensive rats. In hypertensive rats treated with deoxycorticosterone acetate (DOCA), spontaneously hypertensive rats (SHR) and spontaneously hypertensive stroke-prone rats (SHR-sp), the intravenous injection of a specific vasopressin antibody resulted in a transient fall of blood pressure of 11 approximately 25mmHg, while in rats with two-kidney Goldblatt hypertension and normal rats, the blood pressure was not affected. This strongly suggests that ADH contributed to systemic vaso-constriction in DOCA hypertension and spontaneous hypertension in rats.

Transforming activity of Epstein-Barr virus obtained by superinfection of Raji cells

Epstein-Barr virus obtained by superinfection of Raji cells with Epstein-Barr virus recovered from P3HR1 cells (HRI virus) transformed human lymphocytes, but it did not superinfect Raji cells. A human lymphoblastoid cell line, HLB, established by such transformation contained 22 Epstein-Barr virus genomes per cell and Epstein-Barr virus-associated nuclear antigen, and a few cells contained early or viral capsid antigen complexes. Chromosomal analysis revealed that HLB-cells were diploid with normal female karyotypes. Replication of Epstein-Barr virus DNA and inhibition of host cell DNA synthesis were observed in HLB cells after superinfection with HR1 virus.

Formation of N-carbamyl putrescine from citrulline in Escherichia coli

Decarboxylation of citrulline by Escherichia coli enzymes was presented. The N-carbamyl putrescine produced showed the same properties as those of synthesized authentic samples in column chromatography, paper chromatography, and paper electrophoresis.

Mechanisms of infection with Epstein-Barr virus. I. Viral DNA replication and formation of noninfectious virus particles in superinfected Raji cells

Human lymphoblastoid Raji cells, which do not produce virus, supported replication of Epstein-Barr virus (EBV) upon superinfection. Early antigen, viral capsid antigen, and virions were produced in Raji cells superinfected with EBV. Viral DNA replicated under complete inhibition of host cell DNA synthesis to the extent that a few micrograms of EBV DNA were recovered from 107 superinfected Raji cells, corresponding to 5,000 viral genomes/cell. Homology of the synthesized viral DNA to parental EBV DNA was more than 90%. Virions produced by the Raji cells contained a 55S DNA but failed to induce early antigen, viral capsid antigen, and viral DNA synthesis after a second superinfection of Raji cells.

[Relation of TRH test to thyroidal suppression test by triiodothyronine in patients with hyperthyroidism under treatment with antithyroid drugs (author's transl)]

The relation of the TRH test to the T3 suppression test was investigated in 43 patients with hyperthyroidism receiving antithyroid drugs for 6 to 27 months (average 14 months). TRH tests were performed by measuring serum TSH levels before and 15, 30, 45, 60, 90 and 120 minutes after intravenous injection of 500 mug of synthetic TRH. Serum TSH was measured by a double antibody radioimmunoassay. Two weeks later, the T3 suppression test was performed by measuring the 24-hr thyroidal uptake of radioiodine after daily administrations of 75 mug of triiodothyronine for 8 days. All patients under study were in euthyroid state, estimated by serum T3-RSU, T4, T3 and FT4I. The value for 24-h uptake after T3 administration was less than 20% in 18 cases, out of which the response to TRH was normal or exaggerated in 15 cases and was absent or impaired in 3 cases. On the other hand, out of 25 cases with the value of 24-h uptake more than 20%, the response to TRH was absent or impaired in 18 cases and was normal or exaggerated in 7 cases. The results of the TRH test and the T3 suppression test were correlated in 33 out of 43 cases. The responsiveness to TRH and the suppressibility with T3 was dissociated in 10 cases, suggesting the TRH test could not replace the T3 suppression test.