Democratic House leaders, shaken and chagrined by the success of the Republicans in preventing passage of a standby gasoline rationing bill, are considering talking steps to discipline both Republicans and their own troops.

As it applies to their Democratic colleagues, they aren't calling it "discipline." The word is "cohesion."

"I think you'll find when we return in September, the Democratic leadership will be pressing in a very vigorous way for cohesion," Democratic Whip John Brademas (D-Ind.) said.

One of the actions being considered is restricting television coverage to just the debates.

The leadership has decided, as Brademas put it, that "hot-eyed younger Republicans" are playing to newly installed Tv cameras, which carry coverage by satellite to about 4 million people. Should the leadership limit this coverage to debates, it would take away from Republicans the forum of the opening minutes of the season, where any member can speak for one minute on any subject.

While Bredemas and other Democrats were blaming Republicans for "obstructionism" and "negativism," they know the debilitating amendments that put the gas rationing bill in such bad shape that it could not clear Conpress this week required considerable Democratic help to pass. There are 159 Republicans in the House , meaning 50 or 60 Democrats had to join them in order to make a majority.

The Republicans' strategy on the bill was simple. They merely offered amendment after amendment that would aid some broad special-interest group, such as farmers, heating oil users or small businessmen. Democrats who has those groups in their districts found the amendments irresistible.

For instance, one amendment would exempt farmers from conservation plans. Another would require a 1 percent set-aside of diesel fuel for farmers. Another would mandate a 1 percent set-aside for home heating oil users. The result would be a "civil war" among farmers, truckers and home heating oil users if diesel fuel supplies are tight this fall, Rep. Toby Moffett (D-Conn.) said.

To aid restaurant owners and movie theater operators, the House voted to gut the requirement that thermostats in nonresidential buildings be set at on lower than 78 degrees in summer and no higher than 65 degrees in winter.

What the Democratic leaders want to do to stop such splintering is equally simple. They want to stop such amendments from being offered. The method is called "a modified closed rule."

Almost every bill sent to the House floor comes through the Rules Committee, which sets time limits on debate and the terms for consideration of the bill. Untill now, the usual procedure has been "open rules" which means that any amendment germane to the bill is allowed.

But tax bills, considered too complicated to be amended by those not thoroughly familiar with the tax code, are sometimes given "closed rules" forbidding any amendments.

"Modified closed rule" means the Rules Committee will allow only certain amendments to be offered.

The result would be to prevent all but the most important and controversial amendments from being offered, so that Republicans could not pick a bill apart.

But there would be another important political result.

Democrats, particularly younger members in closely contested districts, worry terribly about getting reelected. As a result, they are extremely nervous about offending any interest group well-represented in their districts.

Senior members think their fears are unfounded. "People in my district do not get up in the morning and say, I wonder how John Brademas voted on that agriculture bill yesterday, even if they are farmers," Brademas said.

Nevertheless, with the "modified closure rule," the leadership would insulate those Democrats from choosing between their special interests and the broad national or party interest.

There is little question that the Rules Committee will go along Speaker Thomas P. (Tip) O'Neill Jr. (D-Mass.) appoints Democratic members of Rules, which means he handpicks members, and if they do not vote his way he can "unappoint" them. The Democratic majority on Rules is 2 to 1.

But there is a certain irony to the move. Brademas and Rules Committee Chairman Richard Bolling (D-Mo.) are amonp those Democratic Veterans who worked for years to reform the House and "open up" its procedures. Closed rules was one item they campaigned against.

"In any body, people find ways to exploit the rules, the way the Republicans have," Brademas said, adding that the pendulum swings both ways.

Brademas also said the leadership would be looking closely at how freshmen appointed to key committees did in supporting the leadership on important votes.

And he implicitly threatened the Republicans with a cut in staff, questioning whether staff members should be use to find ways to obstruct legislation. Brademas chairs a House Administration subcommittee that funds committee staffs.

In President Carter's recent Cabinet shakeup "loyalty" was an issue. Asked if the House leadership has caught Carter's loyalty bug," Brademas just smiled.