What does upregulation and downregulation means with regard to the endocrine system?

Answer 1

Gradients,streams and regulations

Electrical gradients--- b/w positive and negative charges, means they like to hold each other to make equilibrium.

eg. ICF with K ions, ICF try to keep K ions inside the cells, As cell is negatively charged and K ions are positively charged.

Concentration gradients--- b/w higher and lower concentration, means they try to maintain same concentration b/w each other.

eg. Osmosis and diffusion,

in osmosis fluid (solvent) moves from higher concentration to lower concentration of solvent through semipermeable membrane.or solvent moves to high solute concentration.

In diffusion solute particles moves from high solute concentration to low solute concentration.

Pressure gradients--- b/w higher and lower pressure, means they try to maintain same pressure b/w each other.

Eg. Beginning of the expiration alveolar pressure is 1mmHg and atm pressure is 0, so in expiration air moves from high pressure to low pressure, ultimately out of body and expiration takes place.

Or inflated balloon has much higher pressure than room pressure, by laplace law less the radius more the pressure, means pressure is inverse to radius so when you leak the balloon air moves from balloon ( higher pressure) to room(low pressure.)

Down gradient---- same as down stream, no need of energy. Natural ways in which all gradients work.

Up gradient--- opposite to down gradient and same as up-stream, needs energy. Against the gradients or natural processes.

Down stream---- simply it means in the direction of flow, or in a natural way as all gradients works. it does not need energy. In other words we can say it's a passive transport.

With an example suppose you swim in a river in the direction of water flow. You do not have to consume your energy because you are in down stream.

Up stream---- simple it directly inverse to down stream, you need energy. In medical view we need ATP to proceed it. Eg. Na/K pump.

Or swim in opposite direction of water flow you can imagine how much energy you will have to spend on it.

Down regulation--- this concept may disrupts you until you are familiar with feedback mechanisms. Down regulation-regulation of anything in order to down. When concentration of any molecules has increased than normal in the ECF then it sends signal to hypothalamus to bring it back to normal or decrease it. It's also a maintaining mechanism in our body.

Eg. When in the blood there is increased level of T3 and T4 , through the signal pathways TSH is decreased in order to drop the level of T3 and T4 or to diminish the production of these. Finally body is trying to maintain equilibrium.

It is more used in pharmacology and biochem.

In other words is same as negative feedback mechanism in endocrine system.

eg. When in the blood there is increased level of T3 and T4 , through the signal pathways TSH is decreased in order to drop the level of T3 and T4 or to diminish the production of these. Finally body is trying to maintain equilibrium.

Up regulation---- just opposite to down regulation. Same as positive feed back mechanism. When something has decresed it will be increased through up-regulation process.

Same example of T3,T4 &TSH can be used to understand it in opposite phenomena.