Single Nephron Hyperfiltration and Proteinuria in a Newly Selected Rat Strain with Superficial Glomeruli

Endothelium-dependent nitric oxide (EDNO) exerts control over the processes of glomerular filtration and tubular reabsorption. The importance of the renal nerves to the tonic influence of EDNO in the glomerular microcirculation and proximal tubule was tested by renal micropuncture in euvolemic adult male Munich-Wistar rats. The physical determinants of glomerular filtration and proximal reabsorption were assessed before and during administration of the nitric oxide synthase inhibitor, NG-monomethyl-L-arginine (L-NMMA), in control animals and in animals 5–9 days after either ipsilateral surgical renal denervation (DNX) or after either sham surgery (SHX). L-NMMA caused single-nephron glomerular filtration rate to decline in control and SHX animals but not in DNX rats. L-NMMA caused a reduction in proximal reabsorption in control and SHX rats, which was prevented by prior DNX. DNX did not alter urinary guanosine 3',5'-cyclic monophosphate excretion, and, although DNX upregulates glomerular angiotensin II (ANG II) receptors, prior DNX did not alter intrarenal ANG II content as evaluated by radioimmunoassay. Some component of renal adrenergic activity is required for the full expression of the glomerular and tubular effects of blockade of nitric oxide synthase.

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Rat strain differences in pilocarpine-induced mouse killing

Physiological Psychology ◽

10.3758/bf03326540 ◽

1976 ◽

Vol 4 (1) ◽

pp. 28-32 ◽

Cited By ~ 6

Author(s):

Patricia E. Gay ◽

Russell C. Leaf

Keyword(s):

Strain Differences ◽

Mouse Killing ◽

Rat Strain

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POSSIBLE ROLE OF 5α-ANDROSTANE-3α,17β-DIOL IN THE CONTROL OF FOLLICLE-STIMULATING HORMONE SECRETION IN THE IMMATURE FEMALE RAT

Journal of Endocrinology ◽

10.1677/joe.0.0920037 ◽

1982 ◽

Vol 92 (1) ◽

pp. 37-42 ◽

Cited By ~ 10

Author(s):

H. M. A. MEIJS-ROELOFS ◽

P. KRAMER ◽

L. GRIBLING-HEGGE

Keyword(s):

Inhibitory Action ◽

Combined Treatment ◽

Hormone Secretion ◽

Inhibitory Effect ◽

Ovariectomized Rats ◽

Female Rat ◽

Immature Rat ◽

Rat Strain ◽

Intact Rats

A possible role of 5α-androstane-3α,17β-diol (3α-androstanediol) in the control of FSH secretion was studied at various ages in ovariectomized rats. In the rat strain used, vaginal opening, coincident with first ovulation, generally occurs between 37 and 42 days of age. If 3α-androstanediol alone was given as an ovarian substitute, an inhibitory effect on FSH release was evident with all three doses tested (50, 100, 300 μg/100 g body wt) between 13 and 30 days of age; at 33–35 days of age only the 300 μg dose caused some inhibition of FSH release. Results were more complex if 3α-androstanediol was given in combined treatment with oestradiol and progesterone. Given with progesterone, 3α-androstanediol showed a synergistic inhibitory action on FSH release between 20 and 30 days of age. However, when 3α-androstanediol was combined with oestradiol a clear decrease in effect, as compared to the effect of oestradiol alone, was found between 20 and 30 days of age. Also the effect of combined oestradiol and progesterone treatment was greater than the effect of combined treatment with oestradiol, progesterone and 3α-androstanediol. At all ages after day 20 none of the steroid combinations tested was capable of maintaining FSH levels in ovariectomized rats similar to those in intact rats. It is concluded that 3α-androstanediol might play a role in the control of FSH secretion in the immature rat, but after day 20 the potentially inhibitory action of 3α-androstanediol on FSH secretion is limited in the presence of oestradiol.

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New homozygous gpt delta transgenic rat strain improves an efficiency of the in vivo mutagenicity assay

Genes and Environment ◽

10.1186/s41021-021-00195-1 ◽

2021 ◽

Vol 43 (1) ◽

Author(s):

Kenichi Masumura ◽

Tomoko Ando ◽

Akiko Ukai ◽

Sho Fujiwara ◽

Shigeo Yokose ◽

...

Keyword(s):

Bone Marrow ◽

Gene Mutation ◽

Point Mutations ◽

Chromosome 1 ◽

Transgenic Rat ◽

Target Tissue ◽

Sequencing Analysis ◽

Rat Strain ◽

Packaging Efficiency

Abstract Background Gene mutation assays in transgenic rodents are useful tools to investigate in vivo mutagenicity in a target tissue. Using a lambda EG10 transgene containing reporter genes, gpt delta transgenic mice and rats have been developed to detect point mutations and deletions. The transgene is integrated in the genome and can be rescued through an in vitro packaging reaction. However, the packaging efficiency is lower in gpt delta rats than in mice, because of the transgene in gpt delta rats being heterozygous and in low copy number. To improve the packaging efficiency, we herein describe a newly developed homozygous gpt delta rat strain. Results The new gpt delta rat has a Wistar Hannover background and has been successfully maintained as homozygous for the transgene. The packaging efficiency in the liver was 4 to 8 times higher than that of existing heterozygous F344 gpt delta rats. The frequency of gpt point mutations significantly increased in the liver and bone marrow of N-nitroso-N-ethylurea (ENU)- and benzo[a]pyrene (BaP)-treated rats. Spi− deletion frequencies significantly increased in the liver and bone marrow of BaP-treated rats but not in ENU-treated rats. Whole genome sequencing analysis identified ≥ 30 copies of lambda EG10 transgenes integrated in rat chromosome 1. Conclusions The new homozygous gpt delta rat strain showed a higher packaging efficiency, and could be useful for in vivo gene mutation assays in rats.

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Detection of specific mRNAs in single nephron segments by use of the polymerase chain reaction

AJP Renal Physiology ◽

10.1152/ajprenal.1990.258.5.f1470 ◽

1990 ◽

Vol 258 (5) ◽

pp. F1470-F1474 ◽

Cited By ~ 4

Author(s):

T. Moriyama ◽

H. R. Murphy ◽

B. M. Martin ◽

A. Garcia-Perez

Keyword(s):

Polymerase Chain Reaction ◽

Aldose Reductase ◽

Collecting Duct ◽

Specific Gene ◽

Rt Pcr ◽

Chain Reaction ◽

Nephron Segments ◽

Single Nephron ◽

Specific Mrnas ◽

Polymerase Chain

We have developed a procedure to detect specific mRNAs in single renal nephron segments. This approach combines microdissection, reverse transcription (RT) of the target mRNA, and amplification of the resulting cDNA using the polymerase chain reaction (PCR). After microdissection, the sample is placed in a tube where it is permeabilized and where all reactions are performed directly without the need for isolation of the RNA. Our model target was the mRNA for aldose reductase. This enzyme catalyzes the conversion of glucose to sorbitol. Its expression is modulated by changes in extracellular osmolality in the renal medulla. RT-PCR of inner medullary collecting duct (1 mm) and glomeruli (6-10) yielded a product of the predicted length (670 base pairs) defined by the PCR primers. Its identity was confirmed by a specific oligonucleotide probe that differed from the primers. RT-PCR of proximal tubules (1 mm) resulted in no aldose reductase-specific amplification product. RT-PCR is generally applicable for measuring specific gene expression in single nephron segments or small numbers of cultured cells. Utility, limitations, and refinements of this approach are discussed.

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