EVALUATION OF BIOLOGICAL LITERATURE
Dopamine Directly Modulates GABA (A) Receptors
Paul Hoerbelt, Tara A. Lindsley, and Mark W. Fleck
Dopamine is known to ligand-gated channels found in invertebrates and activate GPCRs in mammals. Dopamine may, in fact, do the opposite in rats. It was seen that dopamine did not require alpha subunits for activation but did require beta and gamma subunits. Picrotoxin blocked Dopamine instead of GABA (A). Contrary to what was expected bicuculline was able to activate GABA (A) receptors that did not possess an alpha subunit. It is suggested by the results that GABA (A) receptors can be directly inhibited by dopamine. The synaptic release of dopamine can produce an enhance signal at a random active, GABA (A) receptor that does not have an alpha subunit.
Molecular Mechanisms of Microcystin Toxicity in Animal Cells
Alexandre Campos and Victor Vasconcelos
Cyanobacteria produce a very potent or strong hepatotoxin called microcystins. These toxins are very attracted to serines and threonines which are protein phosphatases. This strong attraction causes them to binding and inhibits the phosphatase from normal function. This causes a cascade of inhibitory events in animal cells. They also cause oxidative stress in combination with the inhibition of phosphatases. Microcystins have also be proven to have some sort of interaction with the mitochondria of animal cells, causing the production of dangerous and reactive oxygen species in the cellular environment.
This is important because the mitochondria is an extremely important organelle which provides energy for cells to fuel the entire body. This build-up of free radicals such as superoxide can cause oxidative stress. This oxidative stress can cause damage to proteins and molecules that are responsible for important reactions in the body and are overall responsible for maintaining life and cellular functions. If one can understand how the microcystins cause this build-up then it will become more possible to stop this from occurring.
Harmful algal blooms: causes, impacts and detection
Kevin G. Sellner, Gregory J. Doucette, Gary J. Kirkpatrick
Algae outbreaks are becoming more and more frequent in warmer waters around the US. These outbreaks are known to be caused by many things which include but are not limited to, river flow (water movement) natural circulation, upwelling relaxation. There are many monitoring systems being placed in an attempt to keep this issue under control. This also includes the development of new methods to predict, and test for these algae blooms to help with prevention. With these factors working together it is evident that there will be a better handle on this situation.
If these things are regulated, one should not only focus on how well this does or does not prevent algae outbreaks but also one how it affects other wildlife as well. The goal is not to prevent algae growth all together but to control excessive growth, because there are still many marine organisms who feast on algae, and it may be their only food source or their main food source. How other marine life use the currents of rivers should also be considered, because there are some animals who rely on current during times of reproduction or as a means of transportation.
Effects of Microcystins on fish
Christelle Malbrouck and Patrick Kestemont
Algae release microcystins into the waters they inhabit. In the early stages of life, being exposed to enough microcystins can cause problems during hatching, a lower rate of survival, much slower growth rate and physical abnormalities in the organism. In adult fish, it has been discovered that these microcystins build up in the liver, the muscles, and viscera. This build up in the liver can increase enzyme activity in the organism, along with heart rate, and cause abnormal behavior. This can affect the trophic levels as well because if these fish are eaten by predators they are ingesting the microcystins as well. Further investigation of effects on the trophic levels will be a part of future studies.
The effects of the fish predators after ingestion of "infected fish" should be looked at in future studies. If these toxins build up in the fish muscles and organs, then by the time they are eaten by the predators there is more than likely a high dose present in the fish. How will this high does, taken in by ingestion affect the predators it comes in contact with?
Effects of salinity, temperature and light on the growth and morphology of green planktonic algae
Adam Latala
Green planktonic algae from the Gulf of Gdansk were studied by being cultivated in a solution with a salinity of 0-35 psu. The temperature of the solution was kept at 5-38 degrees C. Based on the environments that these algae usually thrived in, their reactions to the differences were significant. Most of the species thrived from high amounts of intense light (20 -380 uE * m^(-2)*s^(-1)). Planktonic algae in the Gulf of Gdansk live in relatively low salinity water (7-8 psu). Temperature, salinity and light intensity were all used in combination. Most of the species grew the best in fresh water with a low water salinity. In waters with higher salinity, the size of the cell of the green planktonic algae was reduced.
This early study of green algae provides ideal information on various types of algae that could potentially be invasive species in the future. Knowing the specific conditions that these types of algae are able to survive in could help in their prevention and/or removal in the future.