LOS ANGELES, California (CNN)  -- While authorities do not yet know what killed Michael Jackson, the possibility that anesthetics -- particularly the drug Diprivan -- might be involved continues to swell with each new revelation.



Propofol induces a coma, not sleep, an anesthesiologist told CNN.



On Friday, The Associated Press quoted an unnamed law enforcement source saying investigators found Diprivan in Jackson's Holmby Hills home.



A nutritionist, Cherilyn Lee, said earlier in the week that Jackson pleaded for the drug despite being told of its harmful effects.



Sources close to Jackson told CNN's Dr. Sanjay Gupta that the singer, who suffered from a sleep disorder, traveled with an anesthesiologist who would "take him down" at night and "bring him back up" during a world tour in the mid-90s.



The California State Attorney General's office has now said it is helping the Los Angeles Police Department in Jackson's death investigation. The U.S. Drug Enforcement Administration is also looking into the role of drugs, two federal law enforcement sources said.



The drug Diprivan, known by its generic name Propofol, is administered intravenously in operating rooms as a general anesthetic, the manufacturer AstraZeneca said Friday.



"It is neither indicated nor approved for use as a sleep aid," said spokesman Tony Jewell.



The drug works as a depressant on one's central nervous system.



"It works on your brain," said Dr. Zeev Kain, the chair of the anesthesiology department at the University of California Irvine. "It basically puts the entire brain to sleep."



However, once the infusion is stopped, the patient wakes up almost immediately.



"So if you're going to do this, you'd have to have somebody right there giving you the medication and monitoring you continuously," Kain said.



Dr. Hector Vila, chairman of the Ambulatory Surgery Committee for the American Society of Anesthesiologists, said he administers the drug during office procedures such as urology, dentistry and gynecology. It is also the most common anesthetic for colonoscopies, he said.



Both doctors said that while they have heard of the drug being abused by health care professionals, who have ready access to it, they had not heard of it being used as a sleep aid medication.



"Propofol induces coma, it does not induce sleep," Kain said. "I can put you in a coma for as many days as you want. And, in fact, in intensive care units who have patients who are on a ventilator, that's one of the drugs they use."



Dr. Rakesh Marwah, of the anesthesiology department at the Stanford University School of Medicine, said the drug can lead to cardiac arrest without proper monitoring.



"Propofol slows down the heart rate and slows down the respiratory rate and slows down the vital functions of the body," he said.



Not enough carbon dioxide exits the body; not enough oxygen enters. And the situation can cause the heart to abruptly stop.



"[It is] as dangerous as it comes," Kain said. "You will die if you will give yourself, or if somebody will give you, Propofol and you're not in the proper medical hands."



Los Angeles police have interviewed Jackson's cardiologist, Dr. Conrad Murray, who apparently tried to revive the singer after he was found unconscious on June 25.



They also impounded Murray's car, saying it might contain evidence -- possibly prescription medications. Police did not say whether they found anything.



Through his lawyers, Murray has released several statements saying that he would not be commenting until the toxicology results into Jackson's death are released. The tests are due back in two to three weeks, the Los Angeles County coroner said Thursday.



"We are treating all unnamed sources as rumors. And, as we have stated before, we will not be responding to rumors or innuendo," Murray's lawyer, Matt Alford said Friday. "We are awaiting the facts to come out and we will respond at that time. "



The anesthesiologist who accompanied Jackson during the HIStory tour in the mid-'90s also
What drug is "as dangerous as it comes"? What is as dangerous as it comes? What is dangerous without proper guidance? Who says Diprivan found in house? Who went on world tour in the 1990s? Who did sources say Jackson traveled with?
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