Proventricular glands in fowl

Some researchers have already described the fowl proventriculus. However, we believed there was a need for detailed carbohydrate histochemical investigations on the same glands. Moreover, some researchers had erred about the lamina muscularis mucosae. The results of these investigations are as follows. 1. The proventricular glands consist of both superficial and profound gastric glands. 2. The superficial glands are distributed in the lamina propria mucosae while the profound glands exist in the tela submucosa. 3. The superficial glands are simple, branched tubular glands. The columnar glandular cells are arranged in a simple layer and react strongly to PAS, AB (pH 2.5 and 0.5). These appear to be dark purple when they are stained with PAS-AB (pH 2.5). Some other methods have also been tried. 4. Judging from the data 3), the superficial gastric glands contain neutral, weak and strong acids, sulfuric and acid mucopolysaccharides, sialomucin, and II and III neutral mucus type. 5. Glandular cells in the body and basal portions of the superficial gastric glands contain a large number of fine pepsinogen granules. 6. Judging from the data of 3)-5), we believe that the superficial gastric glands are undifferentiated gastric glands and that they are same kinds of glands that are found in mammals. 7. A large number of profound gastric glands fill the tela submucosa. They are compound tubular glands, and are composed of many glandular alveoli. Their columnar glandular cells are arranged in a simple layer. 8. These glandular cells react moderately to PAS, negatively to AB (pH 2.5 and 0.5) and PAS-AB (pH 2.5). Moreover, we observed some other reactions.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of S-8666 on Cl- transport in the rabbit connecting tubule perfused in vitro

S-8666, [6, 7-dichloro-5-(N, N-dimethylsulfamoyl)-2, 3-dihydrobenzofurancarboxylic acid] is a potent diuretic with uricosuric action. Although the major site of action of S-8666 has been proven by the in vitro microperfusion study to be the thick ascending limb of Henle's loop, clearance studies in the rat suggested that this drug has an additional thiazide-like action. To provide direct evidence that S-8666 acts also on distal nephron segments, we examined effect of S-8666 on Cl- flux across the rabbit connecting tubule perfused in vitro. The drug suppressed the lumen-to-bath Cl- flux by 96 +/- 41 (S.E.)pmol.mm-1.min-1 (n = 9) without affecting transmural voltage. To demonstrate that S-8666 acts on the connecting tubule cell, the target of thiazide diuretics, we compared effects of S-8666 and trichlormethiazide on the basolateral membrane voltage of the connecting tubule cell. Both drugs added to the lumen caused a small but significant hyperpolarization of the basolateral membrane without affecting transmural voltage. We conclude that S-8666 is a unique uricosuric diuretic having actions on both thick ascending limb of Henle's loop and connecting tubule.

Bilateral enlargement of the aortic valve ring for valve replacement in children. New operative technique

We report a new technique for the bilateral enlargement of a small aortic anulus in two children by the insertion of a bifurcated teardrop-shaped Dacron fabric lined with a porcine pericardium. Our experience in two children indicates that this technique will permit the insertion of a prosthetic valve that is four sizes larger than that measured with the native anulus intact in children weighing around 15 kg. It entails no risk of distorting the mitral valve, damaging the conduction system, the main coronary arteries or their important trunks, or of leading to left ventricular dysfunction.

Interaction of trichlormethiazide or amiloride with PTH in stimulating Ca2+ absorption in rabbit CNT

To determine the renal tubular site and mechanism of the anticalciuric effects of trichloromethiazide (TCM) and amiloride, we studied the effects of these diuretics on net Ca2+ absorption (JCa) in isolated rabbit connecting tubules (CNT) and cortical collecting ducts (CCD). TCM (100 microM) in the lumen increased JCa in the CNT without affecting lumen-negative transepithelial voltage (VT). This effect was dependent on the amount of parathyroid hormone (PTH, 0.1 or 1 nM) in the bath. TCM had no detectable effect on JCa in the absence of PTH. Addition of 100 microM ouabain to the bath decreased PTH-stimulated JCa and abolished the TCM-stimulated JCa. Elimination of Na+ from the lumen increased PTH-stimulated JCa. Under this condition the ability of TCM to increase JCa was abolished, suggesting that the inhibition of Na+ entry from the lumen with TCM may account for the increase in PTH-stimulated JCa. Elimination of Na+ from the bath in the presence of PTH decreased JCa and abolished the stimulatory effect of TCM on JCa in the presence of PTH. Changes in VT caused by amiloride may not account for the increase in JCa, because JCa was not changed when VT was deflected to more positive direction by increasing bath K+ from 5 to 15 mM. Neither TCM nor amiloride affected JCa in the CCD. From these observations, we speculate that the inhibition of Na+ entry across the apical cell membrane by either thiazides or amiloride may stimulate PTH-induced JCa. The intact Na(+)-Ca2+ antiporter in the basolateral cell membrane is essential for the anticalciuric effect of thiazides and amiloride.

Selectivity of ion permeability across ascending thin limb of Henle's loop: interaction of Cl- and other halogens with anion transport system

In hamster ascending thin limb of Henle's loop (ATL) perfused in vitro, we examined halogen selective permeability and effects on Cl- transport. Relative permeabilities for halogens to sodium (PX/PNa) were determined by single salt dilution voltage. (PF/PNA, PCl/PNa, PBr/PNa and PI/PNa were 0.47 +/- 0.09, 3.23 +/- 0.22, 3.23 +/- 0.26, and 0.47 +/- 0.09, respectively. Simultaneous determination of 36Cl and 125I fluxes confirmed that addition of 10(-4) M 5-nitro-2-(3-phenyl-propylamino)-benzoate (NPPB), a Cl- channel blocker, to the bath decreased the flux coefficient for 36Cl (10(-7) cm2/s) from 67.0 +/- 11.7 to 29.5 +/- 7.9 without affecting that for 125I. NPPB also reduced both PCl/PNa and PBr/PNa from 2.67 +/- 0.20 to 0.95 +/- 0.12 and from 2.33 +/- 0.24 to 1.32 +/- 0.12, respectively. Addition of 100 mM Cl- or I- decreased 36Cl flux coefficient from 124.8 +/- 14.3 to 87.7 +/- 13.0 or to 41.0 +/- 11.6 without affecting that for 125I. All other halogens and SCN- also exhibited inhibitory effects on 36Cl flux. These findings support the hypothesis that the putative Cl- channel in the ATL is highly permeable to both Cl- and Br- but less permeable to I-, F-, and SCN-. They suggest that there are at least two functionally distinct components in the process of Cl- transport across the ATL, the binding site and the selective barrier. All halogens may compete against Cl- at the binding site.

Effect of protamine on ion conductance of upper portion of descending limb of long-looped nephron from hamsters

To estimate the contribution of paracellular shunt pathway to the cation-selective permeability in the upper portion of the descending limb of long-looped nephron (LDLu) of hamsters, we observed the effect of protamine on salt-diffusion voltage (delta VT) and transmural resistance (RT). delta VT generated on reduction of lumen NaCl concentration was decreased from 12.0 +/- 1.4 to 7.3 +/- 1.2 mV when 100 micrograms/ml protamine were added to the lumen. Although the effect of protamine persisted after removal of the agent from the lumen, addition of 30 U/ml heparin reversed the delta VT toward the control level. The effect of protamine was dose dependent in the range from 3 to 1,000 micrograms/ml. Protamine was without effect from the bath. Studies on single salt dilution voltage revealed that 100 and 300 micrograms/ml protamine inhibited relative Na+ to Cl- permeability from 4.03 +/- 0.38 to 2.14 +/- 0.21 and from 3.75 +/- 0.37 to 1.36 +/- 0.09, respectively. Protamine markedly decreased the apparent transference number for Na+ but slightly increased the value for Cl-. Protamine also inhibited permeabilities for K+, Rb+, and Li+ relative to Cl-, indicating that the inhibitory effect of protamine was not confined to Na+ but was generalized to cations. Transmural cable analysis showed that 100 micrograms/ml protamine increased RT from 14.0 +/- 1.1 to 19.3 +/- 1.2 omega.cm2, with the effect being reversed by 30 U/ml heparin. Because the effect of protamine on RT was unaffected by ouabain in the bath, changes in RT may mainly represent those of the paracellular shunt resistance.(ABSTRACT TRUNCATED AT 250 WORDS)

[Enhanced myocardial depression from bupivacaine in diabetic rats]

We examined the direct effects of bupivacaine on the diabetic rat myocardium using an isolated perfused (Langendorff) heart preparation. Rats were made diabetic by injection of streptozotocin (55 mg.kg-1, i. v.). 12 weeks after the administration of streptozotocin, hearts were excised and perfused using Langendorff technique. Following 60 min for equilibration, diabetic hearts from the 12-week animals exhibited significant bradycardia. Bupivacaine 3 mcg.ml-1 did not decrease myocardial contractility in control animals. However, 3 mcg.ml-1 bupivacaine decreased contractility significantly in diabetic animals at nearly all periods. Bupivacaine decreased heart rate and coronary flow significantly and similarly in control and diabetic rats hearts. After pacing at 4 Hz, bupivacaine decreased contractility more in diabetic group than in control group. These results indicate that the presence of a diabetic state appears to enhance the sensitivity of the heart to the myocardial depressant effect of bupivacaine.

Effects of exposure to sulfate aerosols and antigen on breathing curve patterns of guinea pigs

We investigated the effects of ammonium sulfate aerosols on asthmatic dyspnea (immediate type) induced by repeated inhalation of a mixture of bovine serum and egg albumin and on the nonspecific responsiveness of the airway tract to acetylcholine. Guinea pigs were exposed to sulfate aerosol in concentrations of 0.2, 0.4, and 2.0 mg/m3 and to 0.2 mg/m3 sulfate aerosol combined with 0.1 ppm of SO2. The exposure time was 2 h/d, 5 d/wk, 38 times in all. The animals were successively exposed to aerosol (for 2 h) and, after 30 min, to the spraying of albumin solution 3 times per week, 7 or 9 times in all. Breathing curves were continuously recorded by a body plethysmograph system during the sensitization periods. The experiments showed that the degree of asthmatic dyspnea in guinea pigs was increased by the exposure to aerosol, and that there is a quantitative relation between the severity of the dyspnea and extent of the exposure. Exposure in the combination with SO2 showed no effect at the concentration studied. Following the exposure experiment, each group of animals was exposed to the spraying of acetylcholine. The sensitivity to acetylcholine increased at aerosol concentrations of 0.4 and 2.0 mg/m3.

Actual characteristics of the glands distributed in the lamina propria mucosae of the fowl esophagus

We performed histological and histochemical investigations on the glands distributed in the lamina propria mucosae of the fowl esophagus and demonstrated their actual characteristics. 1. Glandular cells of the compound tubular glands located in the lamina propria mucosae contained a number of fine pepsinogen granules. 2. Reactions to neutral, weak and strong acid mucopolysaccharides, neutral mucus type II and III and sialomucin were evidently positive in these cells. 3. Based on the facts in 1) and 2), we consider that the glands located in the fowl esophagus are undifferentiated gastric glands. 4. The same glands possessed no parietal cells. 5. We demonstrated that the esophageal cardiac glands in the lamina propria mucosae of human esophagus were undifferentiated gastric glands, and they possessed parietal cells. These glands were confirmed in humans alone among the mammalia. 6. The significance of the existence of the same kind of gland in human and fowl esophagus is extremely important. 7. PAS-positive substance in the above-mentioned glands in the fowl esophagus contains sulfuric, acid, neutral mucopolysaccaride and neutral mucus of type II and III but no glycogen. The compound tubular glands distributed in the lamina propria mucosae of the fowl esophagus have been described as mucous glands. We performed histochemical investigation and demonstrated that these glands were undifferentiated gastric glands.

Evaluation of the antimicrobial activity of methylglyoxal bis(guanylhydrazone) analogues, the inhibitors for polyamine biosynthetic pathway

Metabolic and antiproliferative effects of methylglyoxal bis(butylamidinohydrazone) (MGBB) and methylglyoxal bis(cyclopentylamidinohydrazone) (MGBCP), inhibitors for polyamine biosynthetic pathway, on Escherichia coli, Shigella sonnei, Aeromonas sobria, Aeromonas hydrophila and Vibrio cholerae were investigated. MGBB at the concentration of 100 mumol/l depleted intracellular putrescine and spermidine concentrations of E. coli to 25 and 20% of the controls, respectively, while MGBCP depressed their concentrations to 38 and 24%, respectively. In these polyamine-depleted E. coli cells the syntheses of RNA, DNA and protein decreased to 13, 54 and 29% of the control, respectively, with MGBB and to 23, 71 and 55%, respectively, with MGBCP. The minimum inhibitory concentrations (MIC) of MGBB for the growth of A. sobria, E. coli, A. hydrophila, V. cholerae and Sh. sonnei were estimated to be 50, 160, 240, 285 and 320 mumol/l, respectively, whereas those of MGBCP were slightly higher for respective bacteria.

Establishment and characterization of immortalized non-transplantable mouse mammary cell lines cloned from a MMTV-induced tumor cell line cultured for a long duration

During the culturing of a mouse mammary tumor cell line, MuMT73, maintained in vitro for more than a decade, we found morphological heterogeneity in its cells; some showed contact inhibition in their growth, some formed domes and some grew criss cross and piled up. In trying to clone the cell line to isolate cells showing contact inhibition or dome formation, we were able to establish six clonal cell lines. These six cell lines were categorically divided into three groups according to their phenotypical behavior, Groups A, B and C. Group A (clones 1, 5 and 7) cells had a property of contact inhibition. They induced no tumor when injected into the subcutaneous tissue of the back, nor even when injected into the mammary fat pads or under the kidney capsule of syngenic or nude mice, and therefore were thought to be non-malignant in nature. They were positively stained by anti-keratin antiserum and had mouse mammary tumor viruses (MMTVs). Group B (clone 6) cells grew in a crisscross pattern and piled up, and they induced tumors when injected into the subcutaneous tissue of the back of mice. Group C (clones 3 and 4) cells formed domes in their growth and induced some tumors in the mammary fat pads and under the kidney capsule of KSN nude mice. In Southern blots with MMTV-env probe, numerous exogenous MMTV proviruses were detected in these cell lines. The insertion patterns of these proviruses in cells of non-malignant clonal lines (Group A) resembled those of malignant lines (Group B), except one band (about 26 Kb), but were considerably different from those of intermediate lines (Group C). On the other hand, no difference was detected in Southern blots with int-1 or int-2 probes among the non-malignant, intermediate and malignant clonal cell lines.

Electrophysiological characterization of upper portion of descending limb of long-looped nephron

The upper portion of the descending limb of long-looped nephron (LDLu) of the hamster is characterized by high water and ion permeabilities. Although the paracellular route is considered to be the major pathway representing cation permselectivity of this segment, ion transport mechanisms through the transcellular pathway are unknown. To study this issue; we applied cable analysis and conventional microelectrode technique to the hamster LDLu perfused in vitro. The transmural voltage (VT) was not different from zero, and transmural resistance (RT) was very low, 18.3 +/- 2.0 omega.cm2 (n = 12). The basolateral membrane voltage was -80 +/- 2 mV (n = 55), and fractional apical membrane resistance was 0.92 +/- 0.23 (n = 5). Ouabain (0.1 mM) in the bath decreased basolateral membrane voltage (VB) by 23 +/- 3 mV (n = 6, P less than 0.001). Increase in K+ concentration in bath and in lumen from 5 to 50 mM decreased VB by 39 +/- 2 (n = 7, P less than 0.01) and apical membrane voltage (VA) by 10 +/- 1 mV (n = 7, P less than 0.001), respectively. Addition of 2 mM Ba2+ to bath and to lumen decreased VB by -47 +/- 2 (n = 11, P less than 0.001) and decreased VA by 8 +/- 1 mV, respectively. Reduction of HCO3- in bath from 25 to 2.5 mM decreased VB by 4 +/- 1 mV (n = 7, P less than 0.005). Reduction of bath Cl- did not cause any rapid deflection of VB. No appreciable Na+ conductance was detected in the apical membrane.(ABSTRACT TRUNCATED AT 250 WORDS)

Congenital mitral regurgitation associated with total anomalous pulmonary venous drainage. Report of a rare combination

A case of congenital mitral regurgitation associated with total anomalous pulmonary venous drainage, successfully treated surgically, is reported. To our knowledge, this combination has not been reported in the literature.

[The effect of orthography and imagery on recall of stimulus items which were read aloud]

The purpose of this study was to compare Kanji items with Kana ones in terms of the free recall performance, and to investigate the effect of orthography and imagery on memory. Two experiments were conducted in incidental learning paradigm, in which subjects were instructed to read aloud each stimulus item. In Experiment 1, an immediate recall test was used. Number of correct free recall for low imagery items was larger in Kanji than in Kana, and this result agreed with Yokoyama and Imai (1989). In Experiment 2, 30-s delay was inserted between a reading aloud task and a recall test. The recall performance indicated superiority of Kanji items in high imagery items. These results were interpreted that the recall process was different between in Kanji items and in Kana ones.

Bactericidal effect of 15-deoxyspergualin on Staphylococcus aureus

15-Deoxyspergualin (DSG), an immunosuppressive agent used in organ transplantation, exerts metabolic and antiproliferative effects on methicillin- and gentamicin-resistant Staphylococcus aureus and other bacteria (e.g. Sarcina lutea, Bacillus subtilis, Shigella sonnei, Salmonella typhi and Citrobacter freundii). DSG, at the concentration of 20 mg/l, depleted intracellular putrescine and spermidine in S. aureus to 43 and 40% of the controls, respectively. In these polyamine-depleted S. aureus cells, the synthesis of protein, DNA and RNA was decreased to 20, 85, 78% of the controls. The minimal inhibitory concentrations (MIC) of DSG for growth of S. aureus, S. lutea, B. subtilis, S. sonnei, S. typhi and C. freundii were 17, 13, 7, 15, 4, and 29 mg/l, respectively.

[Crossed cerebellar diaschisis demonstrated by SPECT in hemiplegic children]

Crossed cerebellar diaschisis (CCD) in twenty five children with hemiplegia were studied using single photon emission computed tomography (SPECT) with N-isopropyl-p-I-123-iodoamphetamine. Seven of twenty-five patients had cerebral palsy, and the others were impaired by acquired brain injury between ten months and fourteen years of age. CCD was demonstrated in five patients (20%), who were impaired by acquired brain injury after seven years of age. CCD could never be detected in patients with cerebral palsy. Ipsilateral cerebellar diaschisis was also demonstrated in two patients with cerebral palsy and three with early acquired brain injury before three years of age. It is suggested that diaschisis presents itself as a different form in a contralateral and ipsilateral cerebellum before three years of age from a form which presents after seven years of age.

Electrophysiological identification of alpha- and beta-intercalated cells and their distribution along the rabbit distal nephron segments

By cable analysis and intracellular microelectrode impalement in the in vitro perfused renal tubule, we identified alpha- and beta-intercalated (IC) cells along the rabbit distal nephron segments, including the connecting tubule (CNT), the cortical collecting duct (CCD), and the outer medullary collecting duct in the inner stripe (OMCDi). IC cells were distinguished from collecting duct (CD) cells by a relatively low basolateral membrane potential (VB), a higher fractional apical membrane resistance, and apparent high Cl- conductances of the basolateral membrane. Two functionally different subtypes of IC cells in the CCD were identified based on different responses of VB upon reduction of the perfusate Cl- from 120 to 12 mM: the basolateral membrane of beta-IC cells was hyperpolarized, whereas that of alpha-IC cells was unchanged. This is in accord with the hypothesis that the apical membrane of beta-IC cells contains some Cl(-)-dependent entry processes, possibly a Cl-/HCO3- exchanger. Further characterization of electrical properties of both subtypes of IC cells were performed upon lowering bath or perfusate Cl- from 120 to 12 mM, and raising bath or perfusate K+ from 5 to 50 mM. A 10-fold increase in the perfusate K+ had no effect on VB in both subtypes of IC cells. Upon abrupt changes in Cl- or K+ concentration in the bath, a large or a small depolarization of the basolateral membrane, respectively, was observed in both subtypes of IC cells. The electrical properties of alpha- and beta-IC cells were similar among the distal nephron segments, but their distribution was different: in the CNT, which consists of IC cells and CNT cells, 97.3% (36/37) of IC cells were of the beta type. In the CCD, which consists of IC cells and CD cells, 79.8% (79/99) of IC cells were of the beta-type, whereas in the OMCDi 100% (19/19) were of the alpha type, suggesting that the beta type predominates in the earlier and the alpha type in the later segment.

The AT richness and gid transcription determine the left border of the replication origin of the E. coli chromosome

We have identified novel, cis-acting elements which enhance in vivo the replication activity of plasmids carrying the minimal oriC of Escherichia coli. These are (i) the AT rich sequence ('AT-cluster') which exists immediately left of the 13mer repeats and (ii) the gid transcriptional unit. The 'AT-cluster' was functionally replaced by an unrelated AT rich sequence. This was also the case for the left and middle 13mers; they were substituted by the AT rich fragment from mini-F plasmid. The left 13mer was replaced by the AT rich sequence which did not show the 'reduced helical stability' known as the important character of the 13mer region. In contrast to these results, the right 13mer sequence was strictly required. As to the effect of the transcription from the gid promoter, the minimal oriC was activated only when the transcription was directed away from the left side of it. mioC transcription proceeding toward the oriC had no effect on the activation. Mutations in the DnaA boxes were partially suppressed by gid transcription leaving oriC from the left side. From these results, we propose that the AT richness is a determinant to identify the left border of oriC. It is presumed that gid transcription introduces negative superhelicity at the AT rich region and facilitates DnaA dependent duplex opening.

Do the cardiac glands exist? 7. The cow

The glands distributed in the narrow region of the abomasum contiguous to the omasum of the cow have been described as cardiac glands. We doubted this assertion and therefore performed histological and histochemical investigations of the glands to clarify their characteristics. 1. All glandular cells except the parietal cells in a few glands contiguous to the omasum react strongly to PAS, AB(pH 2.5), and PAS-AB(pH 2.5) staining, and moderately to AB(pH 0.5) staining. 2. Glandular cells at the base of these glands contain fine pepsinogen granules and a few parietal cells are distributed in these glands, indicating that they are undifferentiated gastric glands and that the so-called cardiac glands do not exist in the cow stomach. 3. Glandular cells in undifferentiated gastric glands are filled with PAS, AB(pH 2.5 and 0.5) and PAS-AB(pH 2.5) positive substances. Which gradually decrease and finally disappear with differentiation, remaining only in the neck (mucous neck cells) and the cells in the upper part of the glandular body (immature chief cells), in mature gastric glands. 4. Mature chief cells in differentiated gastric glands are distributed in the middle and lower bodies and base of the glands and contain a number of PAS and PAS-AB(pH 2.5) positive granules and a large number of coarse pepsinogen granules, while pepsinogen granules in the mucous neck cells and immature chief cells are finer. 5. In the cow the region in which undifferentiated gastric glands are located is very narrow. 6. Parietal cells in the cow stomach are numerous.(ABSTRACT TRUNCATED AT 250 WORDS)

[Partial closure of the atrial septal primum defect and biventricular repair for a case of hypoplastic right ventricle with partial atrioventricular canal defect]

An eight-year-old girl with partial atrioventricular canal defect and hypoplastic right ventricle was treated successfully by a palliative open-heart surgery. The preoperative right ventricular pressure was 58/7 mmHg (RVP/LVP = 0.67) and morphology of the right ventricle showed severe tricuspid stenosis and small outflow portion. The preoperative RVEDVI was 31 (41% of normal and tricuspid annulus was 17 mm (47% of normal). The right ventricular outflow was reconstructed with insertion of MVOP and the ASD was partially left open (the amplitude of the interatrial communication was 7 mm). Angiocardiogram two and half years after the operation demonstrated significant right ventricular growth with no right to left shunt through interatrial communication. The RVEDVI was 46 (56% of normal) and tricuspid annulus was 36 mm (90% of normal). This technique can be a procedure of choice in patient with right ventricular hypoplasia, who is not candidate for simple right ventricular reconstruction nor Fontan procedure, as the growth of the right ventricule is expected in the future.

[Coats' disease and familial retinal arteriolar tortuosity]

The first Japanese autosomal dominant pedigree of familial retinal arteriolar tortuosity was presented with photographical documentation. The proband, a 7-year-old girl also had typical Coats' disease in her left eye. The fluorescein fundus angiogram revealed retinal telangiectasis and microaneurysms with dye leakage in her left peripheral eyeground and marked arteriolar tortuosity without dye leakage in posterior portions of both eyegrounds. Her father showed prominent retinal arteriolar tortuosity bilaterally, and her sister and paternal grandmother showed mild tortuosity of retinal arterioles in both eyes. The recently proposed hypothesis that the familial retinal arteriolar tortuosity is caused by the retinal microcirculatory disturbance consisting of increased resistance in the retinal capillary bed might explain the coincidental occurrence of retinal arteriolar tortuosity and Coat's disease in this report.

Comparative histology and histochemistry of the gastric glands of cats and dogs

We performed histological and histochemical investigations on the gastric glands of cats and dogs. So-called cardiac glands in the cat and dog have a small number of the parietal cells and the PAS-positive glandular cells in the base of these glands contain fine pepsinogen granules. Consequently, we consider them as undifferentiated gastric glands, and can find no differences between these glands in both animals. The immature chief cells in the cat gastric glands are distributed not only in the glandular body but also in the base of the glands and contain sialomucin, and weak and strong acid mucopolysaccharides. The mature chief cells in cat and dog gastric glands contain weak and strong acid mucopolysaccharides. The gastric gland region of the dog is divided into clear and dark zones, and structural differences between the two zones are recognizable. Namely, the chief cells in the glandular base in the clear zone are somewhat undifferentiated, while the chief cells in the middle and lower parts of the glandular body and those in the glandular base in the dark zone are perfectly differentiated. The structure of the gastric glands in the fundic and greater and lesser curvature regions in the cat is very similar.