Influence of age and sex on the concentrations of thyroid hormone in serum in the rat

Studies of the influence of age and sex on the concentrations of total thyroxine (T4) and 3,5,3′-tri-iodothyronine (T3) in serum and on the free T4 and free T3 indices, were conducted in Sprague–Dawley rats of the CD strain varying in age between 10 days and 12 months. Both sex- and age-related differences were found. In all age-groups studied, serum T4 concentrations were higher in the male than in the female, whereas serum T3 concentrations were higher in the female. In both sexes, concentrations of T4 and T3 in serum reached a peak early in life, between the first and second month of age, and declined thereafter. In addition, in both sexes the intensity of thyroid hormone binding, as judged from values of the in-vitro uptake of T3, did not change with age, suggesting that free T4 and T3 concentrations in the serum display the same sex differences and age-related changes as do the concentrations of total T4 and T3. It remains to be determined whether these sex-and age-related alterations in serum thyroid hormone concentration are expressed in differences in the activity of various thyroid hormone-dependent processes.

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Age-related decline in the taurine content of the skin in rodents

Amino Acids ◽

10.1007/s00726-021-02956-2 ◽

2021 ◽

Author(s):

Tomohisa Yoshimura ◽

Yuki Inokuchi ◽

Chikako Mutou ◽

Takanobu Sakurai ◽

Tohru Nagahama ◽

...

Keyword(s):

High Performance ◽

Age Groups ◽

Immunohistochemical Analysis ◽

Sprague Dawley ◽

Taurine Supplementation ◽

Hairless Mice ◽

Age Related ◽

Sprague Dawley Rats ◽

High Concentrations ◽

Effects Of Aging

AbstractTaurine, a sulfur-containing amino acid, occurs at high concentrations in the skin, and plays a role in maintaining the homeostasis of the skin. We investigated the effects of aging on the content and localization of taurine in the skin of mice and rats. Taurine was extracted from the skin samples of hairless mice and Sprague Dawley rats, and the taurine content of the skin was determined by high-performance liquid chromatography (HPLC). The results of the investigation revealed that the taurine content in both the dermis and epidermis of hairless mice declined significantly with age. Similar age-related decline in the skin taurine content was also observed in rats. In contrast, the taurine content in the sole remained unchanged with age. An immunohistochemical analysis also revealed a decreased skin taurine content in aged animals compared with younger animals, although no significant differences in the localization of taurine were observed between the two age groups. Supplementation of the drinking water of aged mice with 3% (w/v) taurine for 4 weeks increased the taurine content of the epidermis, but not the dermis. The present study showed for the first time that the taurine content of the skin decreased with age in mice and rats, which may be related to the impairment of the skin homeostasis observed with aging. The decreased taurine content of the epidermis in aged animals was able to be rescued by taurine supplementation.

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Role of thyroxine on postnatal development of ileal active bile salt transport

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1986.251.2.g237 ◽

1986 ◽

Vol 251 (2) ◽

pp. G237-G242 ◽

Cited By ~ 1

Author(s):

J. E. Heubi

Keyword(s):

Thyroid Hormone ◽

Postnatal Development ◽

Active Transport ◽

Salt Transport ◽

Maximal Velocity ◽

Sprague Dawley ◽

Sprague Dawley Rats ◽

Taurocholate Transport

The role of thyroid hormone on the postnatal development of ileal active taurocholate transport uptake was measured by an in vitro incubation technique in Sprague-Dawley rats. In 16-day-old rats treated with pharmacological doses of L-thyroxine (50 micrograms X 100 g body wt-1 X day-1 on days 10-13), ileal active transport appeared precociously whose Km was 1.60 +/- 0.48 mM and Vapp (apparent maximal velocity) was 8.09 +/- 1.14 nmol X min-1 X mg dry wt-1, while age-matched shams had only passive diffusion of taurocholate. To determine whether enhanced endogenous secretion of thyroxine was capable of stimulating development of ileal active taurocholate transport, thyrotrophic stimulating hormone (TSH) (0.5 U/100 g body wt twice daily) was given on days 10-13, with uptake measured on day 16. Following TSH treatment, only passive transport for taurocholate was observed in the ileum; uptake rates were consistently higher than those for untreated controls at each study concentration. Thyroidectomy performed at age 14 days with uptake measured at age 21 days did not ablate development of ileal active transport but resulted in a significant reduction (P less than 0.001) in the Vapp (7.39 +/- 1.10 nmol X min-1 X mg dry wt-1) and a significant increase (P less than 0.014) in Km (1.72 +/- 0.53 mM) compared with age-matched controls. Thyroid hormone does not appear to be obligatory for the postnatal development of ileal active taurocholate transport.

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Ontogeny of vasoconstrictor neurohypophysial hormone function in rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1990.258.1.r263 ◽

1990 ◽

Vol 258 (1) ◽

pp. R263-R268 ◽

Cited By ~ 1

Author(s):

L. K. Kullama ◽

V. Balaraman ◽

J. R. Claybaugh ◽

W. M. Ichimura ◽

K. T. Nakamura

Keyword(s):

Arginine Vasopressin ◽

Age Groups ◽

In Vitro Study ◽

Progressive Increase ◽

Arginine Vasotocin ◽

Sprague Dawley ◽

Response Curves ◽

Solution Ph ◽

Age Related

This in vitro study examined the ontogeny of arginine vasopressin (AVP) and arginine vasotocin (AVT) compared with norepinephrine (NE)-mediated contraction in rat thoracic aortas. Aortas from three age groups (2-3 days, 6-7 days, and 12 wk) of Sprague-Dawley rats were used. Ring segment resting length was adjusted to optimize tension developed to a dose that produces half-maximal tension of NE in Krebs solution (pH 7.4, 37 degrees C) and gassed with 95% O2-5% CO2. Cumulative dose-response curves were generated for KCl (5-100 mM), NE (10(-10)-10(-5) M), AVP, and AVT (both 10(-10)-10(-6) M) in the presence and absence of a selective V1 vasopressinergic inhibitor, [1-(beta-mercapto-beta,beta-cyclopentamethylenepropionic acid), 2-(O-methyl)tyrosine]arginine vasopressin ([d(CH2)5Tyr(Me)]AVP). A progressive increase in sensitivity among all age groups was found for KCl and NE. There was a slight decrease in sensitivity to both AVP and AVT in the 1st wk. Maximum contractile response to NE increased between 2-3 and 6-7 days, whereas no change was observed for KCl, AVP, or AVT. AVP- and AVT-mediated contractions were selectively inhibited by [d(CH2)5Tyr(Me)]-AVP. These results suggest 1) receptor-mediated contractility is present from 2 days of age for NE, AVP, and AVT; 2) sensitivity to KCl and NE increases progressively during postnatal development, whereas sensitivity to AVP and AVT slightly decreases in the 1st wk with no progressive age-related increase by 12 wk; 3) AVP and AVT mediate contraction via a similar V1-like receptor.

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Effects of a Proprietary StandardizedOrthosiphon stamineusEthanolic Leaf Extract on Enhancing Memory in Sprague Dawley Rats Possibly via Blockade of Adenosine A2AReceptors

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2015/375837 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Annie George ◽

Sasikala Chinnappan ◽

Yogendra Choudhary ◽

Vandana Kotak Choudhary ◽

Praveen Bommu ◽

...

Keyword(s):

Social Memory ◽

Recognition Task ◽

Ethanolic Extract ◽

Social Recognition ◽

Sprague Dawley ◽

Short Term ◽

Antagonist Activity ◽

Age Related ◽

Sprague Dawley Rats

The aim of the study was to explore a propriety standardized ethanolic extract from leaves ofOrthosiphon stamineusBenth in improving impairments in short-term social memoryin vivo,possibly via blockade of adenosine A2Areceptors (A2AR). The ethanolic extract ofO. stamineusleaves showed significantin vitrobinding activity of A2AR with 74% inhibition at 150 μg/ml and significant A2AR antagonist activity with 98% inhibition at 300 μg/mL. A significant adenosine A1receptor (A1R) antagonist activity with 100%inhibition was observed at 300 μg/mL. Its effect on learning and memory was assessed via social recognition task using Sprague Dawley rats whereby the ethanolic extract ofO. stamineusshowed significant (p<0.001) change in recognition index (RI) at 300 mg/kg and 600 mg/kg p.o and 120 mg/kg i.p., respectively, compared to the vehicle control. In comparison, the ethanolic extract ofPolygonum minusaerial parts showed small change in inflexion; however, it remained insignificant in RI at 200 mg/kg p.o. Our findings suggest that the ethanolic extract ofO. stamineusleaves improves memory by reversing age-related deficits in short-term social memory and the possible involvement of adenosine A1and adenosine A2Aas a target bioactivity site in the restoration of memory.

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Pharmacological comparison of four biopolymeric natural gums as hemostatic agents for management of bleeding wounds: preliminary in vitro and in vivo results

Future Journal of Pharmaceutical Sciences ◽

10.1186/s43094-021-00237-z ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Himanshu Kushwah ◽

Nidhi Sandal ◽

Meenakshi Chauhan ◽

Gaurav Mittal

Keyword(s):

Xanthan Gum ◽

Guar Gum ◽

Human Lymphocytes ◽

Sprague Dawley ◽

Gum Tragacanth ◽

Civilian Trauma ◽

Sprague Dawley Rats ◽

Cytotoxicity Studies

Abstract Background Uncontrolled bleeding is one of the primary reasons for preventable death in both civilian trauma and military battle field. This study evaluates in vitro and in vivo hemostatic potential of four biopolymeric natural gums, namely, gum tragacanth, guar gum, xanthan gum, and gum acacia. In vitro evaluation of whole blood clotting time and erythrocyte agglutination assay were carried out. In vitro cytotoxicity studies with respect to each gum were done in human lymphocytes to ascertain percent cell viability. In vivo hemostatic potential of each gum (as sponge dressing and powder form) was evaluated in Sprague Dawley rats using tail bleeding assay and compared with commercially available hemostatic sponge. Other important parameters like (a) time taken for complete hemostasis, (b) amount of blood absorbed, (c) adherence strength of developed hemostatic dressing(s), (d) incidence of re-bleeding, and (e) survival of animals were also studied. Results Of the four test gums studied, xanthan gum (@3mg/ml of blood) and gum tragacanth (@35mg/ml of blood) were able to clot blood in least time (58.75±6.408 s and 59.00±2.082 s, respectively) and exhibited very good hemostatic potential in vitro. Except for xanthan gum, all other test gums did not exhibit any significant cytotoxicity at different time points till 24 h. In rat tail bleeding experiments, gum tragacanth sponge dressing and powder achieved hemostasis in least time (156.2±12.86 s and 76±12.55 s, respectively) and much earlier than commercially available product (333.3±38.84 s; p˂0.01). Conclusion Results indicate potential of gum tragacanth to be developed into a suitable hemostatic product.

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Bioavailability in Vivo of Benzo[a]Pyrene Adsorbed to Diesel Particulate

Toxicology and Industrial Health ◽

10.1177/074823379100700302 ◽

1991 ◽

Vol 7 (3) ◽

pp. 125-139 ◽

Cited By ~ 6

Author(s):

David R. Bevan ◽

David M. Ruggio

Keyword(s):

Health Risks ◽

Quantitative Description ◽

Intratracheal Instillation ◽

Direct Analysis ◽

Sprague Dawley ◽

Reasonable Estimate ◽

Diesel Particulate ◽

Sprague Dawley Rats

To evaluate health risks associated with exposure to particulates in the environment, it is necessary to quantify the bioavailability of carcinogens associated with the particulates. Direct analysis of bioavailability in vivo is most readily accomplished by adsorbing a radiolabeled form of the carcinogen to the particulate. A sam ple of native diesel particulate collected from an Oldsmobile die sel engine that contained 1.03 μ g benzo[ a] pyrene ( BaP)/ g particulate was supplemented with exogenous [ 3 H]- BaP to pro duce a particulate containing 2.62 μ g BaP/g. To insure that elu tion of BaP from native and [3 H] -BaP-supplemented particulate was similar, in vitro analyses were performed. When using phos pholipid vesicles composed of dimyristoylphosphatidylcholine (DMPC), 1.52% of total BaP was eluted from native particulate into the vesicles in 18 hrs; from [ 3 H] -BaP supplemented particu late, 1.68% was eluted. Using toluene as eluent, 2.55% was eluted from native particulate, and 8.25% from supplemented particulate, in 6 hrs. Supplemented particulate was then instilled intratracheally into male Sprague-Dawley rats and distribution of radioactivity was analyzed at selected times over 3 days. About 50% of radioactivity remained in lungs at 3 days following instil lation, with 30% being excreted into feces and the remainder dis tributed throughout the organs of the rats. To estimate the amount of radioactivity that entered feces through swallowing of a portion of the instilled dose, [3 H] -BaP-supplemented particu late was instilled intratracheally into rats that had a cannula sur gically implanted in the bile duct. Rate of elimination of radio activity into bile was monitored; 10.6% of radioactivity was re covered in 6 hr, an amount slightly lower than the 12.8% ex creted in 6 hrs into feces of animals with intact bile ducts. Our studies provide a quantitative description of the distribution of BaP and its metabolites following intratracheal instillation of diesel particulate. Because rates of elution of BaP in vitro are similar for native diesel particulate and particulate with supple mental [ 3H] -BaP, our results provide a reasonable estimate of the bioavailability in vivo of BaP associated with diesel particu late.

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Effects of TRPC6 Inactivation on Glomerulosclerosis and Renal Fibrosis in Aging Rats

Cells ◽

10.3390/cells10040856 ◽

2021 ◽

Vol 10 (4) ◽

pp. 856

Author(s):

Eun Young Kim ◽

Stuart E. Dryer

Keyword(s):

Renal Function ◽

Protective Effect ◽

Renal Fibrosis ◽

Transient Receptor Potential ◽

Smooth Muscle Actin ◽

Receptor Potential ◽

Sprague Dawley ◽

Age Related ◽

Sprague Dawley Rats ◽

Transient Receptor

Canonical transient receptor potential 6 (TRPC6) channels have been implicated in familial and acquired forms of focal and segmental glomerulosclerosis (FSGS) in patients and animal models, as well as in renal fibrosis following ureteral obstruction in mice. Aging also evokes declines in renal function owing to effects on almost every renal compartment in humans and rodents. Here, we have examined the role of TRPC6 in driving inflammation and fibrosis during aging in Sprague-Dawley rats. This was assessed in rats with non-functional TRPC6 channels owing to CRISPR-Cas9 deletion of a portion of the ankyrin repeat domain required for the assembly of functional TRPC6 channels (Trpc6del/del rats). Wild-type littermates (Trpc6wt/wt rats) were used as controls. Animals were evaluated at 2 months and 12 months of age. There was no sign of kidney disease at 2 months of age, regardless of genotype. However, by 12 months of age, all rats examined showed declines in renal function associated with albuminuria, azotemia and increased urine excretion of β2–microglobulin, a marker for proximal tubule pathology. These changes were equally severe in Trpc6wt/wt and Trpc6del/del rats. We also observed age-related increases in renal cortical expression of markers of fibrosis (α-smooth muscle actin and vimentin) and inflammation (NLRP3 and pro-IL−1β), and there was no detectable protective effect of TRPC6 inactivation. Tubulointerstitial fibrosis assessed from histology also appeared equally severe in Trpc6wt/wt and Trpc6del/del rats. By contrast, glomerular pathology, blindly scored from histological sections, suggested a significant protective effect of TRPC6 inactivation, but only within the glomerular compartment.

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Safety Assessment of a Hydroethanolic Extract of Caralluma fimbriata

International Journal of Toxicology ◽

10.1177/1091581813492827 ◽

2013 ◽

Vol 32 (5) ◽

pp. 385-394 ◽

Cited By ~ 3

Author(s):

Antoinette Y. Odendaal ◽

Narendra S. Deshmukh ◽

Tennille K. Marx ◽

Alexander G. Schauss ◽

John R. Endres ◽

...

Keyword(s):

Developmental Toxicity ◽

Toxicity Study ◽

Developmental Study ◽

Sprague Dawley ◽

Oral Toxicity ◽

Toxicological Assessment ◽

Sprague Dawley Rats ◽

Chromosomal Aberration Test ◽

Hydroethanolic Extract

This toxicological assessment evaluated the safety of a hydroethanolic extract prepared from Caralluma fimbriata (CFE), a dietary supplement marketed worldwide as an appetite suppressant. Studies included 2 in vitro genotoxicity assays, a repeated dose oral toxicity study, and a developmental study in rats. No evidence of in vitro mutagenicity or clastogenicity surfaced in the in vitro studies at concentrations up to 5000 μg of extract/plate (Ames test) or 5000 μg of extract/mL (chromosomal aberration test). No deaths or treatment-related toxicity were seen in the 6-month chronic oral toxicity study in Sprague-Dawley rats conducted at 3 doses (100, 300, and 1000 mg/kg body weight (bw)/d). The no observed effect level for CFE in this study was considered to be 1000 mg/kg bw/d. A prenatal developmental toxicity study conducted at 3 doses (250, 500, and 1000 mg/kg bw/d) in female Sprague-Dawley rats resulted in no treatment-related external, visceral, or skeletal fetal abnormalities, and no treatment-related maternal or pregnancy alterations were seen at and up to the maximum dose tested. CFE was not associated with any toxicity or adverse events.

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