Diet & Atmosphere Condition Description


The biological themes we are pursuing are airway responsiveness, blood pressure regulation, lung function and renal function in response to acute and chronic hypoxia and chronic changes in salt content of the diet as well as other acute stressors. These phenotypes will be genetically mapped and compared to each other to define interactions at the physiological level. Animals are conditioned for 2 to 3 weeks, depending on protocol, by varying salt level in their diet or their atmospheric conditions. Diets contain either 0.4% NaCl (low salt), 4.0% NaCl or 8.0% NaCl (high salt). Atmospheric conditions are either 12% inspired oxygen (hypoxia) or 21% inspired oxygen (normoxia).


Effect of Diet*

Diet and Phenotypes
Diet composition in rat chow types significantly influences several phenotypes measured in the PhysGen phenotyping protocols, including salt-sensitive hypertension and renal disease. Rats fed a purified AIN-76A diet exhibited more renal glomerular and tubular damage than rats fed a grain-based diet. For additional information related to these findings, please see Influence of diet and genetics on hypertension and renal disease in Dahl salt-sensitive rats and Dietary Protein Source Determines the Degree of Hypertension and Renal Disease in the Dahl Salt-Sensitive Rat
   
Supplier Catalog order # Percent NaCl
Dyets Inc. 113755 0.4
Dyets Inc. 113756 4.0
Dyets Inc. 100078 8.0
Teklad 3075S 0.4
Teklad TD01454 4.0

* MCW does not have an interest in, or endorse any particular rat chow supplier

Diet Condition Description

Animals are fed 0.4%, 4.0% or 8.0% NaCl diet for 17 days to 3 weeks before entering phenotyping protocol, as specified in each protocol manual.

LN(L-NAME) is Nomega-Nitro-L-Arginine Methyl Ester Hydrochloride.
FHH and FHH.BN consomic animals in the Renal protocol receive L-N(12mg/L in drinking water) for 17 days prior to surgery in addition to the 8.0% NaCl diet that they receive for 17 days before entering the protocol.
FHH and FHH.BN consomic animals in the histology high salt + L-N protocol receive L-N (12mg/L) in drinking water for the last 17 days in addition to the 8.0% salt diet that they receive for 17 days.

Diet Type

Diet Type Description

Cc
Conversion period. Moms had mixed diet, Dyets and Teklad, for 3-4 weeks. Whatever Mom was fed, so were pups. Whatever pups were fed in the barrier, they continued with through the study. Possible maternal influence on pups estimated at 10 weeks
Dd
Moms and pups used in studies were fed Dyets
Td
Moms were fed Teklad, pups used in studies were fed Dyets
Tt
Moms and pups used in studies were fed Teklad
Vd
Moms were fed vendors standard diet, pups were fed Dyets upon arrival at MCW. For rats received from Harlan
Vt
Moms were fed vendors standard diet, pups were fed Teklad upon arrival at MCW. For rats received from CRL and Harlan

Atmosphere Condition Description

HYPOXIA, 12% inspired oxygen for 2 weeks before entering phenotyping protocol.
NORMOXIA, 21% inspired oxygen prior to entering phenotyping protocol.