Cardiophys: Preventing Genetic Destiny Flashcards
What explanation is there for the variance seen in the blood pressure of people in the population?
Half the variance can be explained by genes.
The rest by family and individual environment.
What are the kind of genetic influences that impact blood pressure?
Rare coding sequence variants (1/1000 people from the population would have these)
Common non-coding variants (they somehow affect the coding DNA) (5% of population to 50%)
What difference to normal blood pressure do the rare coding variants have on blood pressure? What about the common non-coding variants?
5mmHg
What are the non-coding variants that exist?
Transcription Factors
Enhancers
Silencers
Insulators
Non-coding RNAs
What are epigenetic changes?
Changes that are not directly due to the code sequence but are instead due to other factors relating to DNA (eg methylation)
What happens to blood pressure as life progresses?
Blood pressure increases with age with a rapid increase right after birth and during puberty
What happened to renin levels in the group in which both parents and offspring had high blood pressure? What was seen in the kidneys?
Plasma renin levels were highest in the group where both parents and offspring had high blood pressure. The kidneys showed the highest vascular resistance in this group as well.
*potentially due to sympathetic activity
What were the differences observed between SHR rats and WKY rats in BP GFR and plasma renin?
BP and renin were higher in SHR
GFR was lower in the SHRs
What kind of problems did SHRs have?
renin-dependent renin abnormalities?
What are SHRs?
Spontaneously hypertensive rats
What happened to SHRs that were given perindopril?
They experienced permanently lower BPs
What is perindopril?
An ACE inhibitor
What ages were correlated with the permanent reduction of BP by perindopril the most?
The effect was most potent when the SHR were young (during puberty)
Less effective during adulthood
Would humans experience the same BP reducing effect that SHRs experienced?
Probably not:
Other animal strains did not experience a permanent drop in BP including other rat strains such as Milan rats.
What are some long term physiological mechanisms for increase in BP?
Vascular structure changes
Sympathetic nervous system activity
Reduced angiotensinogen
Renal function
