Differential alteration of adenylyl cyclase subtypes I, II, and V/VI in postmortem human brains of heroin addicts

In animal and culture cell experiments, the upregulation of cAMP-related signal transduction after chronic opioid administration has been hypothesized to be an adaptive change of the molecular mechanism to maintain homeostasis in intracellular signals downstream from opioid receptors. Herein, we have examined the quantitative changes of three adenylyl cyclase (AC) subtypes (I, II, and V/VI) in temporal cortex membranes from brains of heroin addicts and age-matched controls by immunoblotting. The immunoreactivity of AC-I decreased significantly (p < 0.05) in heroin addicts, compared with controls; whereas those of AC-II and AC-V/VI were not changed. The present findings indicate that differential regulation of AC subtypes occurs and that AC-I may play an important role in the signal transduction for opiate-induced tolerance and dependence mechanisms in human brain cortex.

Targeted inactivation of Npt2 in mice leads to severe renal phosphate wasting, hypercalciuria, and skeletal abnormalities

Npt2 encodes a renal-specific, brush-border membrane Na+-phosphate (Pi) cotransporter that is expressed in the proximal tubule where the bulk of filtered Pi is reabsorbed. Mice deficient in the Npt2 gene were generated by targeted mutagenesis to define the role of Npt2 in the overall maintenance of Pi homeostasis, determine its impact on skeletal development, and clarify its relationship to autosomal disorders of renal Pi reabsorption in humans. Homozygous mutants (Npt2(-/-)) exhibit increased urinary Pi excretion, hypophosphatemia, an appropriate elevation in the serum concentration of 1,25-dihydroxyvitamin D with attendant hypercalcemia, hypercalciuria and decreased serum parathyroid hormone levels, and increased serum alkaline phosphatase activity. These biochemical features are typical of patients with hereditary hypophosphatemic rickets with hypercalciuria (HHRH), a Mendelian disorder of renal Pi reabsorption. However, unlike HHRH patients, Npt2(-/-) mice do not have rickets or osteomalacia. At weaning, Npt2(-/-) mice have poorly developed trabecular bone and retarded secondary ossification, but, with increasing age, there is a dramatic reversal and eventual overcompensation of the skeletal phenotype. Our findings demonstrate that Npt2 is a major regulator of Pi homeostasis and necessary for normal skeletal development.

Immunocytochemical analysis of sex differences in calcitonin gene-related peptide in the rat dorsal root ganglion, with special reference to estrogen and its receptor

Previous studies have shown that the calcitonin gene-related peptide (CGRP) immunoreactivity in the central nervous system (CNS) of adult rats is sexually dimorphic and regulated by sex steroid. In the present study, we used immunocytochemistry to investigate the sex difference in CGRP-immunoreactive (IR) neurons in rat dorsal root ganglia (DRG). The numbers of CGRP-IR neurons at the cervical, lumbar and sacral levels in the female rats were significantly lower than those of the male rats. We also found that the number of CGRP-IR neurons at the lumbar level was increased in ovariectomized (OVX) rats, but was decreased in estradiol (E2)-treated rats (OVX+E2). A large number of estrogen receptor (ER)-IR neurons at the lumbar level were found in the female rats, and its number was greater than that in the male rats. We also investigated the change in the number of ER-IR neurons of OVX rats after estrogen treatment. The number of ER-IR neurons in the OVX+E2 rats was consistent with that of the intact female rats, but was significantly increased in the OVX rats. As shown by a double-labeling immunocytochemical method, over 80% of the CGRP-IR neurons at the lumbar level showed ER immunoreactivity in the female, OVX and OVX+E2 rats, compared to only about 46% in the male rats. These results indicate that there is a gender difference in CGRP expression in the rat DRG, and that this CGRP expression might be downregulated by estrogen (at least in part) through its receptor.

Calcium-sensing receptor in mature osteoclasts, which are bone resorbing cells

Bone metabolism consists of osteoblast-mediated bone formation coupled to osteoclastic resorption of bone. Osteoclastic bone resorption plays an important role in normal skeletal development and the maintenance of its integrity throughout life. Although osteoclastic activity is thought to be under the control of feedback regulation by extracellular cations, the molecular mechanism of detecting extracellular cations within the bone microenvironment remains to be clarified. In the present study we showed by reverse transcription-polymerase chain reaction and Northern blot analysis that cultured mature osteoclasts express the calcium-sensing receptor (CaSR) mRNA. The nucleotide sequence of rabbit osteoclast CaSR was approximately 90% identical to that of CaSR cDNA from human, bovine, and rat parathyroid glands. Moreover, the activity of osteoclastic bone resorption, as determined by pit formation, was regulated by extracellular calcium ion as well as its agonists that are known to act through the CaSR. We conclude that CaSR, homologous to that identified in parathyroid glands, is present in mature osteoclasts and calcium ion released from bone may directly regulate osteoclastic bone resorption.

Measurement of receptor-mediated functional activation of G proteins in postmortem human brain membranes

Guanine nucleotide-binding regulatory proteins (G proteins) play a pivotal role in receptor-mediated transmembrane signal transduction, and have been implicated in modes of action of psychotropic drugs as well as in pathogenesis of psychiatric disorders. In the present investigation, functional activation of G proteins coupled with several receptors, in particular with GABAB receptors, was assessed by agonist-induced stimulation of high-affinity GTPase, an enzyme that is intrinsic to alpha subunit of G protein, in postmortem human frontal cortical membranes. High-affinity GTPase activity was stimulated by GABA as well as (+/-)-baclofen, a selective GABAB receptor agonist, with EC50 values of 60-150 and 10-40 microM, respectively, in a Mg(2+)-dependent manner. The (+/-)-baclofen-stimulated response was antagonized by the selective GABAB receptor antagonist, 2-hydroxy-saclofen, in a competitive manner with a KB value of 59 microM. Although the maximal percent increase above basal value (% Emax) for GABAB receptor-mediated high-affinity GTPase activity was varied from subject to subject, % Emax values for both agonists were highly correlated with each other, and replicable and stable in a given subject, indicating that this measure is trustworthy as an index of functional coupling between receptors and G proteins in future studies at the aim of elucidating possible alteration of receptor/G protein interaction in psychiatric disorders. The % Emax values for GABAB receptor-mediated responses were correlated inversely with brain storage duration, which should be critically considered in postmortem studies. The increases in high-affinity GTPase activity stimulated by several agonists other than GABAB receptor agonists seemed too low to quantify for making a comparison in future studies.

[Experimental glaucoma model in the rat with laser trabecular photocoagulation after intracameral injection of India ink]

We tried to create an experimental glaucoma which is simple and highly reproducible in rodents. India ink was injected into the anterior chamber with a 30-gauge needle. The carbon particles were trapped in the chamber angle and formed a black band along the corneal limbus one week later. This area was then photocoagulated anteroposteriorly with an argon laser. Photocoagulation was repeated until the intraocular pressure was elevated to 25 mmHg or more by pneumotonometry performed at a one-week interval. The above procedure was applied to one eye of 7 rats with the fellow eye serving as control. Chronic elevation of intraocular pressure was obtained in all the 7 treated eyes. The eyes were then enucleated and examined by light microscopy. Carbon particles were phagocytosed by macrophages in the intertrabecular spaces. Peripheral anterior synechias were also present. The optic nerve-head showed remarkable decrease in nerve fibers and cavernous degeneration suggestive of glaucomatous optic nerve damage. This experimental model promises to be of value in further studies of glaucomatous optic nerve damage.

Steroid hormones and their receptors in the brain

Steroid hormones regulate several important functions of the brain by altering the expression of particular genes through their receptors. First in this paper the localization of glucocorticoid receptor immunoreactivity and mRNA in the brain was examined. Second biphasic effects of glucocorticoid on the hippocampus was described and particular emphasis was given on the apoptosis. Third the significance of estrogen receptor in the sexually dimorphic areas was discussed. These results suggest that steroids modulate the gene expression along with the alteration of cell structures in a different manner in a tissue-specific pattern.

Food intake and food consumption patterns of hospital workers in the dominican republic

Coronary heart disease (CHD) is the leading cause of death according to official mortality statistics in the Dominican Republic. The purpose of this study was to assess food intake and food consumption patterns of Dominicans and to discuss CHD risks related to nutrient intake. The subjects were 22 men and 81 women voluntarily recruited among 230 hospital workers in Santo Domingo. The mean nutrient intake and food consumption were estimated from a single 24-hour recall method administered by trained persons who elicited each subject's previous day's intake from midnight to midnight. The mean energy intake was 2030 kcal. The mean intake of total protein, total fat and carbohydrates were 66.3g, 89.1 g and 248g, respectively. Percentage of energy from total fat was 39.5%, which was higher than WHO recommendations. But, the percentage of animal fat per total fat was 46.8%. Especially, the value in the low income group was 31.7%. Moreover, we analyzed the food consumption structure in order to understand the Dominican dietary pattern, and three factors were found to explain the characteristics on the basis of factor analysis.The low percentage of animal fat was due to the diets rich in vegetable oil. Our results suggested that it was difficult to assume that CHD risks increased as a result of the Dominican dietary pattern. This was consistent with our previous findings that the average serum cholesterol level of Dominicans was generally low.

Calcium mobilization evoked by amyloid beta-protein involves inositol 1,4,5-triphosphate production in human platelets

We examined the effects of amyloid beta-protein (A beta) on Ca2+ mobilization in human platelets. The addition of A beta fragments 25-35 (A beta 25-35) gradually increased the cytoplasmic free Ca2+ concentration ([Ca2+]i). After the maximum response, [Ca2+]i decreased and then reached a sustained, higher level of [Ca2+]i. Similar effects were also observed with A beta 1-40, whereas 1-28 , 12-28 and 31-35 did not affect the Ca2+ response. In the absence of extracellular Ca2+, A beta 25-35 caused a transient increase in [Ca2+]i, which returned to the resting level. U73122, a phospholipase C inhibitor, completely abolished Ca2+ mobilization induced by thrombin and A beta 25-35. Furthermore, A beta enhanced the production of inositol 1,4,5-trisphosphate (IP3) in platelets. These findings suggest that Ca2+ mobilization induced by A beta 25-35 is due to phospholipase C activation and IP3 production.

Inguinal cystoceles: a previously overlooked etiology of prostatism in men without bladder outlet obstruction

PURPOSE

We determine whether inguinal cystoceles, a type of extraperitoneal herniation of the bladder, are responsible for symptoms consistent with prostatism in men without bladder outlet obstruction.

MATERIALS AND METHODS

From January 1996 to February 1997 inguinal cystoceles were treated with surgical repair of the floor of the inguinal canal in 8 men with a relatively long history of symptoms consistent with prostatism. The diagnosis of inguinal cystoceles was based on the filling phase of video urodynamic studies done with the patient standing. The clinical outcome of surgery was assessed using the International Prostate Symptom Score and urodynamic findings.

RESULTS

All inguinal cystoceles studied were physically occult but clearly detected as wide-mouthed, mild protrusions of the bladder wall in the inguinal region on cystograms obtained with the patient standing. Although clear cystoceles were present on radiography on the right side in 1 case, the left side in 2 and bilaterally in 5, apparent bilateral weakness in Hesselbach's triangle was noted in all at surgery. High detrusor opening pressure and a relatively long opening time were regarded as urodynamic parameters characteristic of this condition. These parameters and subjective symptoms dramatically improved after bilateral surgical repair of the floor of the inguinal canal.

CONCLUSIONS

Inguinal cystoceles negatively affect voiding dynamics by increasing opening pressure and opening time, indicating that they should be considered in the differential diagnosis of men with symptoms consistent with prostatism. Video urodynamics is mandatory to detect this condition, which to our knowledge has been previously overlooked on radiography and urodynamics.

Effect of age on physiologic and mechanically stressed rat alveolar bone: a cytologic and histochemical study

The effect of age on physiologic and mechanically stressed rat alveolar bone was assessed with special focus on bone formation and resorption in maxillary molar sections of 1-, 4-, 9-, 16-, and 24-month-old male Fischer rats. Tetracycline- and calcein-labeled undecalcified sections were used for observation by confocal laser scanning microscopy and contact microradiography. The localization of osteoclasts and the morphological change of osteoblasts were observed on decalcified sections. Mechanical stress was applied by an orthodontic elastic inserted between the first and second maxillary molars for 7 days. Results showed that bone-formative activity of osteoblasts and bone-resorptive activity of osteoclasts declined with age around the maxillary molar section of physiologic rat alveolar bone. However, results of mechanically stressed rat alveolar bone revealed no evidence of numerical difference in number, size, and activity of osteoclasts and osteoblasts among the ages, suggesting that mechanical stress provokes a higher activity of osteoblasts and osteoclasts similarly in both adult and younger rat alveolar bone.

Peripheral blood lymphocytes from psoriatic patients are hyporesponsive to beta-streptococcal superantigens

The strong association of acute guttate psoriasis and streptococcal throat infection, together with the preferential use of T cells expressing a particular T-cell receptor, has suggested a role for bacterial superantigens in the pathogenesis of psoriasis. We examined the proliferative responses of peripheral blood lymphocytes (PBLs), obtained from patients with psoriasis and from healthy controls, to streptococcal superantigens, cytoplasmic membrane-associated protein (CAP) and secretion-type CAP (SCAP), isolated from group A, beta-haemolytic streptococci. PBLs from patients with psoriasis showed significantly less response to SCAP and CAP than those from healthy controls. Because there was no difference between psoriatic patients and controls in the proliferative response of PBLs to staphylococcal enterotoxin A or E (SEA, SEE) or the mitogen phytohaemagglutinin (PHA), these findings strongly suggest that the reduced reactivity to the streptococcal superantigens seems to reflect anergy of a population of PBLs to the superantigens. As the CAP used in the present study stimulates V beta 8 T cells selectively, we further examined the proliferation of V beta 8 T cells after such stimulation using flow cytometry. V beta 8 T cells obtained from three of four psoriatic patients failed to proliferate in the presence of CAP, whereas they proliferated vigorously in the presence of SEE, which activates V beta 8 T cells, confirming the specific hyporesponsiveness of PBLs from psoriatic patients to streptococcal superantigens. We then determined the effects of serum factors on the suppressed response of PBLs to the streptococcal superantigens with SCAP or CAP. It was partially restored when PBLs were cultured with sera obtained from healthy subjects, although the responses were still significantly lower than those of the healthy controls. In contrast, psoriatic sera markedly suppressed the proliferative response of PBLs from healthy controls to CAP or SCAP, but showed no suppression of the proliferative response of PBLs to SEA. Because these findings suggest the presence of specific inhibitory factors in psoriatic sera, we examined whether the inhibitory effect was caused by antisuperantigen antibody. However, no significant increase was detected in antibody titre to CAP in psoriatic sera, as has been noted in sera from patients with poststreptococcal glomerulonephritis. The present results show for the first time the hyporesponsiveness of PBLs to streptococcal superantigens and the presence of serum inhibitors that specifically inhibit T-cell response to the superantigens in psoriatic patients. These findings suggest a pathological role for streptococcal infections in the pathogenesis of psoriasis.

Differential effects of chronic administration of the antidepressants amitriptyline and rolipram on adenylyl cyclase activity

Significant increases were observed in guanylylimidodiphosphate- and fluoride-stimulated adenylyl cyclase activities in synaptic membrane preparations from rat cerebral cortex subsequent to the repeated administration of rolipram and amitriptyline. The potency of GppNHp-dependent inhibition of adenylyl cyclase was decreased by chronic treatment with rolipram but not by amitriptyline treatment. These findings suggest that chronically administered rolipram and amitriptyline share the augmentation of adenylyl cyclase activity by different actions on post-receptor signaling.

Immunocytochemical development of transferrin and ferritin immunoreactivity in the human pons and cerebellum

The distribution and development of transferrin-positive cells in the pons and cerebellum of human fetuses to adults were examined immunohistochemically, compared with those of ferritin-positive cells. Transferrin was present in oligodendrocytes, astrocytes, and neurons. Transferrin-positive neurons appeared at 18 weeks of gestation in Purkinje cells and the pontine reticular formation. In the pontine nuclei, transferrin-positive neurons appeared at 22 weeks of gestation. On the other hand, transferrin-positive glia also appeared at 18 weeks of gestation in the reticular formation, and at 24 weeks of gestation in the cerebellar white matter and pontine nuclei. Transferrin-positive glia and cells appeared earlier in the reticular formation of the pons than ferritin, but the order of its appearance was similar to that of ferritin and myelination. Because iron is involved in the syntheses and functions of dopamine, serotonin, and gamma-aminobutyric acid (GABA), transferrin may be carried for various iron uses from an early fetal stage.

[Chronic perianal pyoderma with urethrocutaneous fistula: a case report]

A 65-year-old male was hospitalized because of micturition pain and urinary oozing from several fistulas on the perineal and the left gluteal skin. Oozing had been present for about 50 years, after receiving mass resection of his left scrotum or perineum, and left orchiectomy. The main focus was on the left dorsal site of the anus. Compression around this area produced malodorous grayish pus discharge from many fistulas, although the anus was intact. Although he had histories of spinal caries and renal tuberculosis, both pus and urine cultures showed Staphylococcus spp. and no growth of Mycobacterium tuberculosis. Urethrocystography showed urethral stenosis at bulbar urethra and leakage from a site just proximal to the stenosis. Antibiotics for tuberculosis were administrated for fear of recurrent tuberculosis for 6 months. Cystostomy formation and debridement were performed, followed by en-bloc resection and mesh-skin graft after two weeks. Internal urethrotomy was performed six months after the surgery, and subsequently cystostomy removed. After three and a half years, although there was no local recurrence and no difficulty of urination, he died of cholangio-carcinoma. There are many reports of chronic perianal pyoderma subsequent to hemorrhoid or subcutaneous abscess; however, this might be the first report on a case originating from fistulas in the urinary tract.

Immunoreactive localization of transforming growth factor-beta type II receptor-positive cells in rat tibiae

To identify the target cells of transforming growth factor-beta (TGF-beta) in normal bone tissue, we examined TGF-beta type II receptor expression using immunohistochemistry, reverse transcription-polymerase chain reaction (RT-PCR), and in situ hybridization in young rat tibiae. In the epiphyseal growth plate, the TGF-beta type II receptor cDNA was detected by RT-PCR and, alternatively, the TGF-beta type II receptor protein and mRNA expression were observed in the chondrocytes in the lower part of the proliferative cell layer, and in maturative and hypertrophic cell layers by immunohistochemistry and in situ hybridization. Of these, proliferative and maturative chondrocytes, in particular, revealed strong mRNA expression. In the cortical bone area, immunoreactivity for the TGF-beta type II receptor was detected in the fibroblastic cells near the osteoblasts on the endosteal surface of cortical bone. In conclusion, our findings suggest that target cells of TGF-beta in normal bone tissue could be considered mainly as extracellular matrix-producing chondrocytes and undifferentiated preosteoblasts, and TGF-beta may affect matrix production and differentiation of these cells.

Ca2+/CaM-sensitive adenylyl cyclase activity is decreased in the Alzheimer's brain: possible relation to type I adenylyl cyclase

Immunoreactivities of four subtypes of adenylyl cyclase (AC) (types I, II, IV and V/VI), and basal, forskolin- and Mn(2+)-stimulated AC activities with or without calcium and calmodulin (Ca2+/CaM) were estimated in parietal cortex membranes from cases with dementia of the Alzheimer type (DAT) and age-matched controls. Immunoreactivities of AC-I and AC-II were significantly decreased, but those of AC-IV and AC-V/VI did not change in DAT brains. There was a significant correlation of AC-I immunoreactivity with Ca2+/CaM-sensitive AC activity, but not with the Ca2+/CaM-insensitive activity. Ca2+/CaM-sensitive AC activity was significantly lower in DAT than in the control, indicating that impairment of Ca2+/CaM-sensitive AC-I is clearly involved in the pathophysiology of DAT.

Potential antidepressant properties of forskolin and a novel water-soluble forskolin (NKH477) in the forced swimming test

The mechanisms of the antidepressant activity of forskolin and a novel water soluble forskolin analog (NKH477) were studied using the forced swimming method in rats. Forskolin (0.01-0.1 mg/kg) and NKH477 (0.01-0.1 mg/kg) dose-dependently decreased ratings of immobility, with effects similar to those of amitriptyline treatment. The maximum effects of forskolin and NKH477 were observed at 0.01 mg/kg dose which is 150 more times potent than that (15 mg/kg) of amitriptyline. At a high dose (1.0 mg/kg) of forskolin and NKH477, the duration of immobility was returned to control levels. Forskolin and NKH477 did not influence the spontaneous locomotor activity at intraperitoneal injection doses from 0.01 to 1 mg/kg. Furthermore chronic administration with NKH477 at oral dose from 0.5 to 1.5 mg/kg significantly decreases the duration of immobility. These data indicate that both forskolin and NKH477 have strong antidepressive potency, consistent with the hypothesis that elevation of the cAMP cascade system may have an important role in antidepressive effects.

Urodynamic changes after endoscopic correction of vesicoureteral reflux

Massive bilateral vesicoureteral reflux (VUR) in a 7-year-old girl with spinal scoliosis was successfully treated by endoscopic correction. She was admitted due to a febrile urinary tract infection and urinary incontinence. A cystometrogram demonstrated normal detrusor function during storage. The endoscopic subureteric injection of polytetrafluoroethylene (Teflon) was performed, resulting in the disappearance of the VUR. A postoperative cystometrogram demonstrated overactive detrusor function during storage, necessitating anticholinergic medication. She has been free of febrile urinary tract infections and incontinence for 2 years postoperatively, although self-catheterization is necessary. In a case of neurogenic vesical dysfunction with massive reflux, endoscopic subureteric injection is not only a therapeutic tool, but also a useful diagnostic option for detecting occult detrusor overactivity during storage prior to open surgery.

Adrenalectomy-induced granule cell death is predicated on the disappearance of glucocorticoid receptor immunoreactivity in the rat hippocampal granule cell layer

In this study, we observed the changes of glucocorticoid receptor (GR)-immunoreactivity (ir) and cell death in the rat hippocampal granule cell layer at various periods after adrenalectomy (ADX). Our results revealed that all of the rats shortly after ADX showed a rapid loss of GR-ir and subsequent appearance of degenerating cells in the granule cell layer. One month after ADX, however, about 80% of the rats displayed a restoration of GR-ir and the absence of degenerating cells in the granule cell layer, and this phenomenon was successively noted for 6 months. Hippocampal structural destruction 3 and 6 months after ADX was found in about 20% of the rats with loss of GR-ir in the granule cell layer; the ADX rats with even weak GR-ir in this area had a normal hippocampus. The treatment of rats with synthetic GR agonist, dexamethasone, immediately after ADX prevented the loss of GR-ir and significantly reduced the number of degenerating cells in the granule cell layer. Our results clarified that granule cell death after ADX was necessarily accompanied by the disappearance of GR-ir in the granule cell layer, suggesting that ADX-induced granule cell death is predicated on the loss of GR-ir and that the presence of GR-ir in this area may be important for granule cell survival.

Prevalence of risk factors for coronary heart disease among Dominicans in the Dominican Republic: comparison with Japanese and Americans using existing data

Risk factors of coronary heart disease (CHD) in Dominicans were compared with those of Japanese and Americans for the presumption of prevalence of CHD in about 2000 persons. Dominican adults aged 20 through 76 years were medically examined in 1993. Data of nationally representative Japanese and Americans which included serum lipid levels were compared. Total cholesterol levels(TCH) in Dominicans were lower than those in Americans. High-density lipoprotein cholesterol levels in Dominicans were lower than those in Japanese and Americans. The prevalence of hypertension and current smoking rates in Dominicans were similar to that of Americans and lower than that of Japanese. TCH in Americans have substantially been declining and those in Japanese were inadequate for preventing CHD. The prevalence of CHD in Dominicans may be lower than that of Americans viewed from the recent levels of main risk factors. Community wide health programs have spread to people with hypertension a decrease in the incidence of CHD should occur.

Immunolocalization of CD44 and the ezrin-radixin-moesin (ERM) family in the stratum intermedium and papillary layer of the mouse enamel organ

We studied the immunohistochemical localization of CD44 and the ezrin-radixin-moesin (ERM) family of actin binding proteins in mouse enamel organ, using confocal laser scanning microscopy and transmission electron microscopy to clarify their role in cytoskeletal organization. At the differentiation stage of ameloblasts, immunoreactivity to CD44 was detected on the plasma membrane of the inner enamel epithelium, the stellate reticulum, the stratum intermedium, and the external enamel epithelium. In accordance with the differentiation of preameloblasts into secretory ameloblasts, immunoreactivity increased in the stratum intermedium cells. At the maturation stage, intense immunoreactivity was observed on the papillary layer cells. For the ERM family, the stratum intermedium and the papillary layer cells were stained with anti-ezrin and -radixin monoclonal antibodies but not with the anti-moesin antibody. Electron microscopic observations revealed that CD44, ezrin, and radixin were localized in the region at which preameloblasts came into contact with the stratum intermedium at the differentiation stage. At the secretory and maturation stages, they were concentrated in the microvilli of the stratum intermedium and the papillary layer cells. These findings suggest that the CD44-ezrin-radixin-actin filament system is involved in cell-cell interaction between preameloblasts and the stratum intermedium, and in the cytoskeletal organization of the cells in the stratum intermedium and the papillary layer.

Endoscopic correction of vesicoureteral reflux by subureteric Teflon (polytetrafluoroethylene) injection: review of 6-year experience

BACKGROUND

Endoscopic correction of vesicoureteral reflux (VUR) was first proposed in 1981 and the first series of patients treated by subureteric polytetrafluoroethylene paste injection (STING) was reported in 1984. Although many successful studies, primarily European, have been undertaken since then, this technique has recently been rejected in the United States. In this paper, we report our 6-year experience and discuss indications for this technique.

PATIENTS AND METHODS

Since February 1990, we have used the STING technique to endoscopically correct VUR. In this analysis, 38 ureters in 24 patients (mean age, 47.3 years; range, 7 to 79 years), with at least 1 year of follow-up were included.

RESULTS

The first injection resulted in disappearance of VUR in 34 ureters (89.5%). A second injection was done for 2 failed and 3 recurrent ureters during follow-up, resulting in disappearance of VUR in the 3 recurrent ureters. The final success rates were 100% for both primary VUR and secondary VUR due to neurogenic bladder, but only 55.6% (5/9) for secondary VUR following transurethral resection of bladder tumors. No postoperative early or delayed complications were noted in any case.

CONCLUSION

The procedure is simple and effective for the treatment of all grades of VUR. However, the procedure should be performed after careful consideration of the indications, since theoretically the risk of distant migration of the paste cannot be ignored.

[Mismatch negativity of patients with hydranencephaly]

We examined auditory evoked potentials and passive event-related potentials in two patients with hydranencephaly. In the middle latency response, a Na component was observed in both cases. Mismatch negativity was elicited in response to tone bursts and three patterns of vowel sounds in Patient 1, and three patterns of vowel stimuli in Patient 2. These results implicate the subcortical components of the auditory system in the generation of mismatch negativity.

[Significance of rectal contractions during multichannel urodynamic study]

BACKGROUND

The influence of rectal contractions on urination was examined using multichannel urodynamic study.

METHODS

We reviewed a total of 246 consecutive urodynamic studies. Each study consisted of a uroflow measurement and multi-channel urodynamic study, evaluating total vesical pressure, abdominal (rectal) pressure, subtracted detrusor pressure and perianal electromyography. Rectal contractions were defined as periodic fluctuations over 5 cmH2O in abdominal pressure detected by a rectal balloon catheter. No relationship of these contractions with cough and breathing was observed.

RESULTS

Of the 246 patients, 17 (6.9%) had a positive study for rectal contractions. The patients, who had positive rectal contractions, averaged 70-year-old were older than negative subjects averaged 62-year-old. In multichannel urodynamics, the flow rate was significantly decreased, and electromyographic activity was increased at the moment of each rectal contractions.

CONCLUSIONS

The rectal contractions are not artifactual and may be regarded as one of causes responsible for urinary difficulty in the elderly.

Gracilis urethral myoplasty: preliminary experience using an autologous urinary sphincter for post-prostatectomy incontinence

PURPOSE

We investigated the effect of a neurovascular intact gracilis muscle urethral wrap to restore urinary continence in men with severe stress urinary incontinence after radical retropubic prostatectomy.

MATERIALS AND METHODS

Three men with stress incontinence after radical retropubic prostatectomy and external beam radiation therapy for adenocarcinoma of the prostate underwent gracilis urethral myoplasty. Video urodynamic evaluation and cystourethroscopy revealed Valsalva leak point pressure of less than 40 cm. water and a damaged urinary sphincter mechanism in all 3 patients. One man underwent concomitant ileocystoplasty.

RESULTS

At 6 to 24-month followup all patients reported improved continence. Mean Valsalva leak point pressure increased from 26.3 +/- 3.2 cm. water before to 83.0 +/- 32.1 cm. water after surgery. The gracilis muscle urethral wrap did not have a deleterious effect on erectile function or ambulation. Complications included 1 wound infection.

CONCLUSIONS

An autologous gracilis muscle urinary neosphincter can be constructed in the bulbous urethra in a fashion similar to that of the artificial urinary sphincter with encouraging results in this preliminary series. The gracilis neosphincter may be an alternative to the artificial sphincter, especially in patients at higher risk for complications, such as after radiation and cryotherapy.

Fibroblasts of spinal ligaments pathologically differentiate into chondrocytes induced by recombinant human bone morphogenetic protein-2: morphological examinations for ossification of spinal ligaments

To elucidate the process of ossification in spinal ligaments, an aqueous solution containing recombinant human bone morphogenetic protein (BMP)-2 (40 micrograms/100 microL) was injected into murine ligamenta flava, and the ossification process was analyzed morphologically. In the control group, the solution administered lacked the protein; these flattened ligamentous fibroblasts possessing BMP receptors type IA and type II existed among type I collagen bundles. In the week immediately following the injection of BMP-2, ligamentous fibroblasts began to proliferate, differentiating into alkaline phosphatase-positive chondrocytes surrounded by an extracellular matrix composed of type I and II collagen. By the second week, differentiated chondrocytes of various stages were observed in type II collagen-rich matrix. These chondrocytes showed an abundance of BMP receptors type IA and II. The pathologically induced cartilage was resorbed by chondroclasts, permitting migration of blood vessels and osteogenic cells, as well as providing a site for endochondral ossification. By the third week, BMP-induced ossification had compressed the spinal cord, and by the sixth week, the ligamentous tissue had been almost completely replaced by bone. Ligamentous fibroblasts appeared to possess BMP receptors, as well as the potentiality to differentiate into chondrocytes. BMP receptors were upregulated during chondrification of ligamentous fibroblasts induced by exogenous BMP-2, suggesting that BMPs may play an important role in ossification of spinal ligaments.

Chronic loss of glucocorticoids following adrenalectomy down-regulates the expression of glucocorticoid receptor mRNA in the rat forebrain

In the negative feedback model, loss of endogenous glucocorticoids up-regulates the expression of glucocorticoid receptor mRNA. To elucidate further the effect of chronic lack of glucocorticoids on the expression of glucocorticoid receptor mRNA and protein, in situ hybridization and immunohistochemical methods were used to examine the long-term alteration of glucocorticoid receptor mRNA and its immunoreactivity in the forebrain of adrenalectomized rats. Constant lack of glucocorticoids resulted in marked decrease in the expression of glucocorticoid receptor mRNA and disappearance of glucocorticoid receptor immunoreactivity in many forebrain structures. In particular, in the suprapyramidal blade of the hippocampal granule cell layer and cerebral cortex, many cells showed almost no glucocorticoid receptor mRNA signals. These results suggest that long-term loss of endogenous glucocorticoids down-regulates the levels of glucocorticoid receptor mRNA, leading to reduction in the synthesis of glucocorticoid receptors in the rat forebrain. Therefore, the presence of endogenous glucocorticoids is vital to the continued expression of glucocorticoid receptor mRNA.

[A case of juvenile Huntington's disease presenting dystonia and confirmed by DNA analysis]

We reported a 13-year-old boy with juvenile Huntington disease diagnosed by DNA analysis. Symptoms started with dysarthria at 6 years of age, which was followed by progressive dysgraphia and gait disturbance due to dystonia from 7 years, and by epileptic seizures from 12 years. Magnetic resonance imaging revealed atrophy of the bilateral caudate nuclei and T2- and proton-weighted high intensity area in both putamina. The CAG (cytosine-adenine-guanine) trinucleotide repeat on chromosome 4 p16 was markedly expanded to 81. For a child with dystonia with mental deterioration, juvenile Huntington disease should be considered in the differential diagnosis.

Saccharated ferric oxide (SFO)-induced osteomalacia: in vitro inhibition by SFO of bone formation and 1,25-dihydroxy-vitamin D production in renal tubules

A 60-year-old man with portal hypertensive gastropathy due to type C liver cirrhosis developed severe bone pains, marked hypophosphatemia with inappropriately increased urinary excretion of phosphate (%TRP; 9.6%), and hyperalkaline phosphatasia, after intravenous administration of saccharated ferric oxide (SFO) at a dose of 80-240 mg/week over a period of more than 5 years. The total iron infused was estimated to be more than 25 g. On a diagnosis of SFO-induced osteomalacia, the infusion of iron was immediately discontinued, and phosphate and vitamin D2 (1000 IU/day) were administered. Serum levels of 25-OHD2 increased after 1 week, whereas levels of 1,25-(OH)2D2 did not increase until 3 months later, accompanied by improvement of renal tubular reabsorption of phosphate and gradual improvement of the bone pains. The patient has been doing well for the last 2 years, with normal serum levels of phosphate, calcium, and alkaline phosphatase, without any supplementation of phosphate, vitamin D, or iron-containing agents. In primary culture of neonatal mouse renal tubules, in which 1,25-(OH)2D3 was produced from 25-OHD3 in response to PTH, SFO significantly inhibited PTH-induced production of 1,25-(OH)2D3 at 30 mumol/L, which is attainable in the urine of patients receiving a therapeutic intravenous dose of SFO. Furthermore, SFO decreased the calcium content and inhibited 45Ca incorporation in cultured fetal mouse parietal bones at 3 mumol/L. Such SFO concentration may be transiently observed in the plasma of patients receiving excessive intravenous doses of SFO for a prolonged period. These in vitro findings together with the clinical observations suggest that SFO, after filtration through the glomerulus and reabsorption in the proximal renal tubules, impaired proximal renal tubular function, such as tubular reabsorption of phosphate and 1 alpha-hydroxylase activity, leading to hypophosphatemic osteomalacia. Furthermore, it is highly likely that SFO in the peripheral blood, when transferrin is saturated with iron, may impair bone formation and aggravate osteomalacia. Although SFO-induced osteomalacia is reversible simply by discontinuation of the agent, excessive and prolonged administration of SFO should be avoided.

Generation and characterization of mouse monoclonal antibodies specific for N-linked neutral oligosaccharides of glycoproteins

We generated four monoclonal antibodies (MAbs) specific for asparagine-linked neutral oligosaccharides of glycoproteins by immunizing mice with neoglycolipids, which were derived from glycoproteins by conjugation to phosphatidylethanolamine dipalmitoyl. The binding specificity of these MAbs was determined by an enzyme-linked immunosorbent assay and immunostaining on thin-layer chromatography. The four MAbs designated OMB3, OMB4, OMR5, and OMR6 reacted strongly with the neoglycolipids, Gal beta1-4GlcNAc beta1-2Man alpha1-6(Gal beta1-4GlcNAc beta1-2Man alpha1-3)Man beta1-4GlcNAc-PD, GlcNAc beta1-2Man alpha1-6(GlcNAc beta1-2Man alpha1-3)(GlcNAc beta1-4)Man beta1-4GlcNAc beta1-4GlcNAc-PD, Man alpha1-6Man beta1-4GlcNAc beta1-4(Fuc alpha1-6)GlcNAc-PD, and Man alpha1-3Man beta1-4GlcNAc-PD, respectively, that were used as immunogens. All of these MAbs exhibited a high binding specificity. The epitopes of the MAbs OMB3 and OMB4 were suggested to be nonreducing terminal trisaccharides, Gal beta1-4GlcNAc beta1-2Man-, and nonreducing beta-GlcNAc residues, respectively. MAbs OMR5 and OMR6 showed a highly restricted binding specificity, reacting only with the immunizing neoglycolipids. Subsequently, MAbs OMB3 and OMB4 were shown to react strongly with asialo-alpha1-acid-glycoprotein and asialo-agalacto-alpha1-acid-glycoprotein, respectively, by Western blotting. Furthermore, it was shown that these MAbs reacted specifically with the epitope on Chinese hamster ovary cells by an immunofluorescence technique. MAb OMB4 was also shown to detect the accumulated oligosaccharides with nonreducing terminal beta-GlcNAc residues as granular inclusions in the cultured fibroblasts from a classical Sandhoff disease patient.

The in vivo time course for elimination of adrenalectomy-induced apoptotic profiles from the granule cell layer of the rat hippocampus

Although apoptotic cellular degeneration has been reported to be extremely rapid with the use of in vitro models, the time needed to clear apoptotic neurons in the in vivo brain is unknown. In this study we used a simple morphological approach to solve this problem. Four days after adrenalectomy (ADX), all of the operated rats morphologically displayed hippocampal granule cell apoptosis that was prevented completely by corticosterone replacement immediately after ADX. Therefore, we intravenously injected the rats with corticosterone 4 d after ADX and subsequently maintained them on corticosterone replacement in saline drinking water. This corticosterone replacement could protect healthy granule cells promptly and continuously against hormone-deficient apoptosis, because the normal glucocorticoid receptor immunoreactivity within the granule cell nuclei, which disappeared after ADX, was identified 1 hr after corticosterone replacement was started, and this effect persisted for several days. However, this corticosterone treatment could not prevent the irreversible apoptosis of the already degenerated granule cells at various stages of the same progressive apoptotic process. Then we successively traced the disappearance of apoptotic granule cells throughout the hippocampus at different time points by Nissl and silver staining. Given that the apoptotic cells at the earliest stage of the degenerating process when the ADX rats received corticosterone injection were the last to disappear, the period from corticosterone injection until the disappearance of the last degenerating debris of apoptotic cells was taken to represent the time course for elimination of apoptotic neurons in vivo. We discovered that the elimination of apoptotic granule cells took 72 hr.

Gangliosides involved in activation of rat T lineage cells

Gangliosides have long been known to be involved in T-cell activation. In our previous studies, a unique GMlb-derived ganglioside, GD1c(NeuGc,NeuGc), was shown to be the predominant ganglioside in rat thymocytes and T-cells. Upon the activation of the thymocytes, the amount of GD1c(NeuGc,NeuGc) increases remarkably, and additionally a novel species of GD1b, GD1b(NeuGc,NeuGc), appears as the other major ganglioside (Nohara, et al. (1993) J. Biol. Chem. 268, 24997-25000). In the present study, monoclonal antibodies (MAbs) against these two gangliosides have been generated. The MAb AC1 established by immunizing mice with purified GD1c(NeuGc,NeuGc) reacted strongly with GD1c(NeuGc,NeuGc) and weakly with GD1b(NeuGc,NeuGc) by enzyme-linked immunosorbent assay (ELISA). The other MAb AB1 obtained by immunization with GD1b(NeuGc,NeuGc) showed a strong binding activity to GD1b(NeuGc,NeuGc) and no reactivity to GDlc(NeuGc,NeuGc) by ELISA. Flow cytometry analyses using these MAbs have revealed that an AC1-positive subset exists in a portion of resting CD4+CD8- thymocytes and CD4+ splenic T-cells. When the thymocytes were activated with 12-O-tetradecanoylpholbol-13-acetate (TPA) and calcium ionophore A23187, the proportion of AC1+ cells increased remarkably and were detected not only in CD4+ cells but also in CD8+ cells. An increase in the proportion of AC1+ cells was also seen in activated T-cells. In contrast, AB1-positive cells were only detected in activated thymocytes, not in resting thymocytes, or resting or activated T-cells. These results implicate GD1c(NeuGc,NeuGc) in the activation of thymocytes as well as T-cells, whereas GD1b(NeuGc,NeuGc) appears to be specifically related to the activation of thymocytes.

[Reevaluation of heart disease deaths on death certificates and trends for ischemic heart disease mortality during the last five years in Oita city]

To evaluate heart disease deaths and clarify trends for ischemic heart disease (IHD) mortality during the last five years in Oita City, we reevaluated causes of death on death certificates. In 1993, there were 253,000 people aged 25-74 in Oita City. In this population age group, there were 1,996 deaths from January 1992 through December 1993. Our subjects were 982 deaths recorded as caused by heart disease and IHD related diseases. Subjects were reevaluated on the basis of physician's interview, clinical records and police records. This IHD reevaluation was conducted by the WHO MONICA criteria. The death certificates identified 321 heart disease deaths, of which there were 80 (24.9%) acute myocardial infarctions (AMI), 22 (6.9%) other IHD, 180 (56.1%) heart failures, and 39 (12.1%) other heart diseases. The remaining 61 deaths were caused by other diseases. After reevaluation, 40 'definite' AMI and 60 'possible' AMI were recognized through the MONICA criteria, 86 sudden deaths (SD) which were defined as, 'death within 24 hours of the onset of acute symptoms and without clear signs suggesting what disease was the cause,' were also classified. Assuming that 50% of SD were due to IHD, according to some postmortem autopsy studies, aged-standardized IHD mortality per 100,000 for males was 38.3 per year and for females 17.3 per year in this period. Both mortality rates, 31% for males and 38% for females, were higher than IHD mortality statistics. Moreover, in comparison with IHD mortality estimated by reevaluation of heart disease in Oita City in 1987-88, age-standardized IHD mortality per 100,000 for males has remained basically stable, increasing from 37.8 to 38.4 during the last five years. On the other hand, mortality for females has increased from 11.2 to 17.3. Our results suggest that mortality from IHD actually was about 30% more than mortality statistics, and does not show a declining trend as mortality statistics have stated.

Heart disease deaths on death certificates re-evaluated by clinical records in a Japanese city

In order to estimate the number of deaths from ischemic heart disease (IHD) in a Japanese city, we reevaluated heart disease deaths among residents aged 25-74 years by examining their clinical records. During the 2-year period from 1987 to 1988, 271 deaths among this population were attributed to heart disease. The recorded underlying cause of death was IHD in 96 cases, heart failure in 123 cases, and other heart disease in 52 cases. Re-evaluation of the cause of death yielded 57 cases of acute myocardial infarction (AMI), 85 cases of sudden death, 37 cases of heart disease other than IHD, and 63 cases of non-heart disease. In the remaining cases, there was insufficient information for evaluation. According to some autopsy studies, about 50% of sudden deaths are due to IHD. Thus, 50% of the number of sudden death cases may be added to the total number of IHD deaths. Accordingly, the total number of IHD deaths may have been 100, ie, 57 cases of AMI plus 43 cases of sudden death. The difference between the number of IHD deaths after re-evaluation and the number for which IHD was recorded as the underlying cause was small, with the former only 4% higher than the latter. The number of false-positives was equal to the number of false-negatives, and hence the number of IHD deaths recorded in this area seems to be close to the actual figure. We speculate that more accurate death certification will result in a decrease in the total number of deaths attributable to heart disease, as in 23% of deaths attributed to heart disease the underlying cause of death was not in fact heart disease.

Specific reduction of plasma large, light low-density lipoprotein by a bile acid sequestering resin, cholebine (MCI-196) in type II hyperlipoproteinemia

The effect of a bile acid sequestrant, cholebine (3 g/day), on plasma lipoprotein subfractions was investigated in 16 patients with type II hyperlipoproteinemia. Activities of low density lipoprotein (LDL)-receptor and activities of lecithin:cholesterol acyltransferase (LCAT) and cholesteryl ester transfer protein (CETP) were assayed to address the mechanism of cholebine-induced changes in plasma lipoprotein subfractions. Twelve weeks of treatment with cholebine reduced plasma levels of total cholesterol (TC) and LDL-cholesterol (C) by 8.3 +/- 8.1% (mean +/- S.D.) and 14.4 +/- 11.9%, respectively (P < 0.001), but did not affect plasma levels of high density lipoprotein (HDL)-C. Cholebine significantly reduced plasma levels of LDL1-C (1.019 < d < 1.045) by 22.9 +/- 18.9% (P < 0.001) but did not affect plasma levels of very low density lipoprotein (VLDL)-C, intermediate density lipoprotein (IDL)-C, LDL2-C (1.045 < d < 1.063), HDL2-C, and HDL3-C (d > 1.125). Gradient polyacrylamide gel electrophoresis (PAGE) revealed that cholebine reduced large LDL in plasma but had almost no effects on small LDL and HDL subfractions. Cholebine did not alter the activities of LCAT and CETP. LDL-receptor activities of cultured lymphocytes negatively correlated with the reduction in plasma levels of LDL-C (r = -0.500, P < 0.05), IDL-C (r = -0.581, P < 0.02), and LDL1-C (r = -0.610, P < 0.01), respectively. Thus, cholebine seems to reduce further the plasma levels of IDL and large, light LDL in patients with lower LDL-receptor activities. We conclude that cholebine only reduces plasma levels of large, light LDL. This may be due to the stimulation of hepatic LDL-receptor activity.

Single-photon emission CT and MR findings in Klüver-Bucy syndrome after Reye syndrome

We present the MR and single-photon emission CT findings in a 3-year-old patient in whom Klüver-Bucy syndrome developed after Reye syndrome. MR images showed diffuse brain atrophy, which was predominant in the temporal lobes, and single-photon emission CT scans showed decreased cerebral perfusion in the bilateral temporal lobes and associated cortical areas.

Immunolocalization of tissue non-specific alkaline phosphatase in mice

Immunolocalization of tissue non-specific alkaline phosphatase (TNAP) was examined in murine tissues, employing a specific antiserum to TNAP on frozen sections, 50-micron tissue slices, and paraffin sections. TNAP was detected at high levels in hard tissues including bone, cartilage, and tooth. In bone tissue, the TNAP immunoreactivity was localized on the entire cell surface of preosteoblasts, as well as the basolateral cell membrane of osteoblasts. It was also localized on some resting chondrocytes and most of the proliferative and hypertrophic cells in cartilage. In the incisor, cells of the stratum intermedium, the subodontoblastic layer, the proximal portion of secretory ameloblasts, and the basolateral portion of odontoblasts showed particularly strong immunoreactivity. Immunoreactivity was observed in other soft tissues, such as the brush borders of proximal renal tubules in kidney, on cell membrane of the biliary canalicula in liver and in trophoblasts in the placenta. These immunolocalizations were quite similar to enzyme histochemical localizations. However, neither the submandibular gland nor the intestine, which both exhibited alkaline phosphatase activity by enzyme histochemistry, revealed immunoreactivity for TNAP. Therefore, immunocytohistochemical studies for TNAP enabled us to localize the TNAP isozyme, thus distinguishing it from other isozymes.

Cu, Zn-superoxide dismutase reaction in neonatal pontosubicular neuron necrosis

The immunohistochemical localization and changes in copper/zinc superoxide dismutase (Cu, Zn-SOD) were examined in 14 neonates with pontosubicular neuron necrosis (PSN), as compared with those in 15 controls in which the cytoplasm of neurons and glial cells showed SOD immunoreactivity. In the temporal lobes and hippocampus with PSN, Cu, Zn-SOD reactivity was negative in neurons at 0 and 1 days after birth, but was positive after 5 days of age in 8 of 10 cases. In the pons and cerebellum, SOD-positive neurons appeared soon after birth, but eosinophilic or karyorrhectic neurons were SOD negative. On the other hand, glial cells were positive after birth in all cases of PSN, and their reactivity was increased in the cases of reactive astrogliosis. Early loss of the scavenging system directed at free radicals may lead to neuronal damage, and the induction of Cu, Zn-SOD may act as a defense mechanism against damage of neurons in neonates with PSN. Therefore, oxygen-derived free radicals may be one of the pathogenetic factors of PSN with characteristics of apoptosis in neonates.

Expression of thyrotropin-releasing hormone (TRH) receptor mRNA in somatotrophs in the rat anterior pituitary

A response of growth hormone (GH) to thyrotropin-releasing hormone (TRH) is observed in lower mammals and patients with diseases such as a cromegaly, but not in normal subjects. We have previously demonstrated the existence of intact TRH receptor mRNA in GH-secreting adenoma. To examine whether intact somatotrophs in the anterior pituitary also express TRH receptor, we attempted to localize both TRHR mRNA and GH immunoreactivity simultaneously. In situ hybridization analysis revealed TRHR mRNAs specifically in the anterior pituitary, and 61.1% of the anterior pituitary cells expressed this transcript. Staining for GH and PRL on the same samples showed that the somatotrophs apparently expressed TRHR mRNA and approximately 62.3% and 30.9% of hybridization-positive cells were somatotorophs and mammotrophs, respectively. Moreover, TRHR mRNA level in the somatotrophs expressed as the number of silver grains per cell was equivalent to that in the mammotrophs. These findings demonstrated expression of the TRHR mRNA in somatotrophs in the rat anterior pituitary, and also showed that more than 50% of the TRHR mRNA detected in the anterior pituitary was derived from these cells.

Cell-specific expression of the parathyroid hormone (PTH)/PTH-related peptide receptor gene in kidney from kidney-specific and ubiquitous promoters

The kidney is the major site of expression of the PTH/PTH-related peptide receptor (PTHR) gene. Previously we have shown that the PTHR gene is expressed from two promoters in kidney, an upstream kidney-specific promoter (P1) and a downstream promoter (P2) that is active in a wide variety of tissues. Here, we have used immunohistochemical and transcript-specific in situ hybridization techniques to map the expression of the PTHR gene and protein and to determine the distribution of P1- and P2-driven messenger RNAs in renal tissue. Immunohistochemical and immunoelectron microscopic analysis showed that PTHR protein is expressed on both basolateral and luminal membranes of proximal tubular epithelial cells, strongly suggesting a bipolar mode of action of PTH. Receptor protein also was detected on the surface of glomerular podocytes. Strikingly, immunoelectron microscopic analysis showed that endothelial cells of the peritubular vasculature, but not the glomerular vasculature, contain high levels of PTHR protein. We found that both P1 and P2 are expressed at moderate levels in both cortical and medullary epithelial cells of nephrons, correlating well with the immunohistochemical localization of PTHR protein. However, although abundant transcripts were detected in peritubular endothelial cells with P1-specific and coding sequence probes, P2-specific expression was not observed in these cells. These results provide evidence that the physiological effects of PTH- and/or PTH-related peptide on renal tubular function may be mediated not only through direct effects on epithelial cells but also indirectly through endothelial cell-based signaling. In addition to expression in vascular endothelial cells, high levels of P1-specific, but not P2-specific, PTHR messenger RNA were detected in vascular smooth muscle. Taken together, these experiments provide evidence for strong PTHR gene expression in renal vascular tissues. Moreover, given that previous studies have shown that P2, but not P1, is active in other tissues with an abundant vasculature, our results suggest that regulation of PTHR gene expression in renal vascular tissue is distinct from that of other organs.