Pea Size

When someone thinks about the brain we visualize a grand organ that that enables us to imagine, learn, and build. We tend to think about the brain as a whole but in reality it is made up of different sections that perform different functions and usually overlap. Embedded in the brain is a small structure than one would attribute much to it because of its size. This structure is the pea shaped pituitary gland, sometimes referred to as the “master gland”. This minute structure is responsible for releasing six hormones upon receiving the correct message from the superior hypothalamus.

The hormones released by the pituitary gland are Growth hormone, Thyroid Stimulating hormone, Follicle Stimulating hormone, Luteinizing hormone, Prolactin, Adrenocorticotropic hormone, Antidiuretic hormone and Oxytocin. The amount of these hormones released is especially important because too little or too much can cause serious effects.

Growth Hormone whose function is to increase both muscle and bone size determines height and strength. If excessive amounts of Growth hormone are released by the pituitary gland the result can be Acromegaly in adults, also known as gigantism in children. This disorder involves swelling of the heart, thickness of the skin, and larger than normal body parts such as hands, legs, and face. A tumor in the pituitary gland can cause excess release of Growth hormone because it signals cells in the gland to produce more and more of the hormone. A defective pituitary gland can also be caused by head injury and disease. In contrast a decreased amount of Growth hormone can cause a higher level of fat accumulation in the body and less or weak muscles.

The pituitary gland affects many organs in our bodies and a balance of the Growth hormone is essential for our wellbeing. Who would have thought such a small structure would how so many profound effects. We cannot assume size equals importance when talking about the brain.

 

Heroin, Deadly and Addictive

The drug Heroin is classified as an Opiate meaning it comes from the poppy plant named Papaver Somniferum. The opium poppy is cultivated in the areas of the Middle East mainly in Iran, Afghanistan, and Pakistan an also in areas of South Asia.

Heroin comes mainly in three forms white powder being the most popular, brown powder, and a new form called black tar that was created in Mexico. This drug is especially dangerous because the main mode of use is through injection. Not only is the user getting the bad side effects of the drug but is also exposed to other viruses such as HIV when sharing needles. Heroin can also be snorted and smoked, the least popular method called “chasing the dragon”.

So why is it especially addictive? Well that has to do with the speed; Heroin is quickly metabolized in the body into Morphine and produces an intense rush as it binds to opiate receptors in the brain. In fact Heroin and Morphine are very similar; the only difference is that Heroin has two acetyl groups, which is why the drug it also referred to as Diacetylmorphine. Along with the initial rush comes a euphoric feeling. Other immediate effects are constriction of the pupils, sweating, and a feeling of being alert and drowsy. Almost one fourth of Heroin users will become addicts.

 

Yes Heroin is very addictive, but what makes it so deadly? This drug is dangerous because it leads to quick tolerance. Soon the Heroin user will need to use more and more of the drug to not feel the withdrawal symptoms. Some of those symptoms are depression and intense cravings for the substance.  If more Heroin is used this could lead to a drug overdose which usually kills the person.

Neurons and their love of Glucose

As you may already know brain cells, or neurons specifically “depend almost entirely on glucose”. That desire for glucose arises from the fact that glucose is practically the only type of nutrient that is able to pass through the heavily guarded blood- brain barrier. The only other nutrient that has permission to cross the blood- brain barrier are ketones. Ketones of course are of no use to the demanding and picky neuron, because this nutrient is not nearly as plentiful as the preferred glucose.

The neurons in the brain demand more energy than any other type of cell. Neurons require the energy in the form of glucose, and the body must provide a steady supply at all times. Neurons don’t have the ability to store glucose so the bloodstream has to deliver the nutrient it acquires from carbohydrates found in food.

So the next question is, really neurons need glucose all time? The answer is yes, they need glucose twenty four hours a day seven days a week. This is due to the fact that neurons are always “in a state of metabolic activity”. Your neurons are even at work using energy while you are sleeping.

Wow! So does that mean that if I have a large supply of glucose available I will have more energy? In reality this is what happens when we ingest foods such as chocolate or sugary soft drinks. “You feel an energy boost”, but it is only for a short period of time because soon the insulin from the pancreas removes it from the bloodstream.

Hey, so maybe Neurons do have an excuse to be so demanding of glucose after all. I know I would also be demanding if I was forced to function all the time.